Patric R. J. Östergård's publications

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Monographs

  1. Classification Algorithms for Codes and Designs, P. Kaski and P. R. J. Östergård, Springer, Berlin, 2006.

Journal papers

  1. A new binary code of length 10 and covering radius 1, P. R. J. Östergård, IEEE Transactions on Information Theory 37 (1991), 179-180.
  2. Upper bounds for q-ary covering codes, P. R. J. Östergård, IEEE Transactions on Information Theory 37 (1991), 660-664; and 37 (1991), 1738.
  3. Further results on (k,t)-subnormal covering codes, P. R. J. Östergård, IEEE Transactions on Information Theory 38 (1992), 206-210.
  4. Upper bounds for covering designs by simulated annealing, K. J. Nurmela and P. R. J. Östergård, Congressus Numerantium 96 (1993), 93-111. (a C program)
  5. New upper bounds for the football pool problem for 11 and 12 matches, P. R. J. Östergård, Journal of Combinatorial Theory. Series A 67 (1994), 161-168.
  6. Bounds for binary codes that are multiple coverings of the farthest-off points, H. O. Hämäläinen, I. S. Honkala, S. N. Litsyn, and P. R. J. Östergård, SIAM Journal on Discrete Mathematics 8 (1995), 196-207.
  7. New multiple covering codes by tabu search, P. R. J. Östergård, The Australasian Journal of Combinatorics 12 (1995), 145-155.
  8. Football pools—A game for mathematicians, H. Hämäläinen, I. Honkala, S. Litsyn, and P. Östergård, The American Mathematical Monthly 102 (1995), 579-588.
  9. New single-error-correcting codes, P. R. J. Östergård and M. K. Kaikkonen, IEEE Transactions on Information Theory 42 (1996), 1261-1262.
  10. A combinatorial proof for the football pool problem for six matches, P. R. J. Östergård, Journal of Combinatorial Theory. Series A 76 (1996), 160-163.
  11. The football pool problem, P. R. J. Östergård, Congressus Numerantium 114 (1996), 33-43.
  12. Constructing covering codes by tabu search, P. R. J. Östergård, Journal of Combinatorial Designs 5 (1997), 71-80.
  13. A coloring problem in Hamming spaces, P. R. J. Östergård, European Journal of Combinatorics 18 (1997), 303-309.
  14. A new table of binary/ternary mixed covering codes, P. R. J. Östergård and H. O. Hämäläinen, Designs, Codes and Cryptography 11 (1997), 151-178.
  15. Improved bounds for ternary linear codes of dimension 7, T. A. Gulliver and P. R. J. Östergård, IEEE Transactions on Information Theory 43 (1997), 1377-1381.
  16. Packing up to 50 equal circles in a square, K. J. Nurmela and P. R. J. Östergård, Discrete & Computational Geometry 18 (1997), 111-120.
  17. New constant weight codes from linear permutation groups, K. J. Nurmela, M. K. Kaikkonen, and P. R. J. Östergård, IEEE Transactions on Information Theory 43 (1997), 1623-1630.
  18. Ternary covering codes derived from BCH codes, J. C. Cock and P. R. J. Östergård, Journal of Combinatorial Theory. Series A 80 (1997), 283-289.
  19. New upper bounds for binary covering codes, P. R. J. Östergård and M. K. Kaikkonen, Discrete Mathematics 178 (1998), 165-179.
  20. Bounds on mixed binary/ternary codes, A. E. Brouwer, H. O. Hämäläinen, P. R. J. Östergård, and N. J. A. Sloane, IEEE Transactions on Information Theory 44 (1998), 140-161.
  21. On the structure of optimal error-correcting codes, P. R. J. Östergård, Discrete Mathematics 179 (1998), 285-287.
  22. Greedy and heuristic algorithms for codes and colorings, T. Etzion and P. R. J. Östergård, IEEE Transactions on Information Theory 44 (1998), 382-388. (codes and colorings in digital form)
  23. Dense packings of congruent circles in a circle, R. L. Graham, B. D. Lubachevsky, K. J. Nurmela, and P. R. J. Östergård, Discrete Mathematics 181 (1998), 139-154.
  24. Improved bounds for quaternary linear codes of dimension 6, T. A. Gulliver and P. R. J. Östergård, Applicable Algebra in Engineering, Communication and Computing 9 (1998), 153-159.
  25. New linear codes with covering radius 2 and odd basis, A. A. Davydov and P. R. J. Östergård, Designs, Codes and Cryptography 16 (1999), 29-39.
  26. Constructing covering codes with given automorphisms, P. R. J. Östergård and W. D. Weakley, Designs, Codes and Cryptography 16 (1999), 65-73.
  27. New coverings of t-sets with (t+1)-sets, K. J. Nurmela and P. R. J. Östergård, Journal of Combinatorial Designs 7 (1999), 217-226. (coverings in digital form)
  28. Optimal binary one-error-correcting codes of length 10 have 72 codewords, P. R. J. Östergård, T. Baicheva, and E. Kolev, IEEE Transactions on Information Theory 45 (1999), 1229-1231. (codes in digital form)
  29. Asymptotic behavior of optimal circle packings in a square, K. J. Nurmela, P. R. J. Östergård, and R. aus dem Spring, Canadian Mathematical Bulletin 42 (1999), 380-385.
  30. New constructions for q-ary covering codes, P. R. J. Östergård, Ars Combinatoria 52 (1999), 51-63.
  31. Covering t-sets with (t+2)-sets, K. J. Nurmela and P. R. J. Östergård, Discrete Applied Mathematics 95 (1999), 425-437.
  32. More optimal packings of equal circles in a square, K. J. Nurmela and P. R. J. Östergård, Discrete & Computational Geometry 22 (1999), 439-457. (search data)
  33. New quaternary linear codes with covering radius 2, A. A. Davydov and P. R. J. Östergård, Finite Fields and Their Applications 6 (2000), 164-174.
  34. On saturating sets in small projective geometries, A. A. Davydov and P. R. J. Östergård, European Journal of Combinatorics 21 (2000), 563-570.
  35. Classification of binary/ternary one-error-correcting codes, P. R. J. Östergård, Discrete Mathematics 223 (2000), 253-262. (codes in digital form)
  36. On sliding block puzzles, F. R. W. Karlemo and P. R. J. Östergård, Journal of Combinatorial Mathematics and Combinatorial Computing 34 (2000), 97-107.
  37. Classification of binary covering codes, P. R. J. Östergård and W. D. Weakley, Journal of Combinatorial Designs 8 (2000), 391-401. (codes in digital form)
  38. Enumeration of 2-(12,3,2) designs, P. R. J. Östergård, The Australasian Journal of Combinatorics 22 (2000), 227-231.
  39. Computer search for small complete caps, P. R. J. Östergård, Journal of Geometry 69 (2000), 172-179.
  40. New binary linear codes, T. A. Gulliver and P. R. J. Östergård, Ars Combinatoria 56 (2000), 105-112.
  41. Improved bounds for ternary linear codes of dimension 8 using tabu search, T. A. Gulliver and P. R. J. Östergård, Journal of Heuristics 7 (2001), 37-46.
  42. Linear codes with covering radius R=2,3 and codimension tR, A. A. Davydov and P. R. J. Östergård, IEEE Transactions on Information Theory 47 (2001), 416-421.
  43. Recursive constructions of complete caps, A. A. Davydov and P. R. J. Östergård, Journal of Statistical Planning and Inference 95 (2001), 167-173.
  44. There exists no (15,5,4) RBIBD, P. Kaski and P. R. J. Östergård, Journal of Combinatorial Designs 9 (2001), 227-232; reprinted in 9 (2001), 357-362.
  45. There are 270,474,142 nonisomorphic 2-(9,4,6) designs, P. R. J. Östergård, Journal of Combinatorial Mathematics and Combinatorial Computing 37 (2001), 173-176.
  46. Values of domination numbers of the queen's graph, P. R. J. Östergård and W. D. Weakley, Electronic Journal of Combinatorics 8(1) (2001), #R29, 19pp.
  47. Error-correcting codes over an alphabet of four elements, G. T. Bogdanova, A. E. Brouwer, S. N. Kapralov, and P. R. J. Östergård, Designs, Codes and Cryptography 23 (2001), 333-342. ((new) clique program)
  48. Bounds on codes over an alphabet of five elements, G. T. Bogdanova and P. R. J. Östergård, Discrete Mathematics 240 (2001), 13-19. ((new) clique program)
  49. On the size of optimal binary codes of length 9 and covering radius 1, P. R. J. Östergård and U. Blass, IEEE Transactions on Information Theory 47 (2001), 2556-2557.
  50. A new algorithm for the maximum-weight clique problem, P. R. J. Östergård, Nordic Journal of Computing 8 (2001), 424-436. ((new) clique program)
  51. A fast algorithm for the maximum clique problem, P. R. J. Östergård, Discrete Applied Mathematics 120 (2002), 197-207. ((new) clique program)
  52. Bounds and constructions for ternary constant-composition codes, M. Svanström, P. R. J. Östergård, and G. T. Bogdanova, IEEE Transactions on Information Theory 48 (2002), 101-111. ((new) clique program)
  53. A new lower bound for the football pool problem for six matches, P. R. J. Östergård and A. Wassermann, Journal of Combinatorial Theory. Series A 99 (2002), 175-179.
  54. Enumeration of 2-(9,3,λ) designs and their resolutions, P. R. J. Östergård and P. Kaski, Designs, Codes and Cryptography 27 (2002), 131-137. (designs in digital form)
  55. A 2-(22,8,4) design cannot have a 2-(10,4,4) subdesign, P. R. J. Östergård, Designs, Codes and Cryptography 27 (2002), 257-260.
  56. Classifying subspaces of Hamming spaces, P. R. J. Östergård, Designs, Codes and Cryptography 27 (2002), 297-305. (codes in digital form)
  57. Ternary constant weight codes, P. R. J. Östergård and M. Svanström, Electronic Journal of Combinatorics 9(1) (2002), #R41, 23pp.
  58. Self-dual and maximal self-orthogonal codes over F7, M. Harada and P. R. J. Östergård, Discrete Mathematics 256 (2002), 471-477.
  59. Classification of extremal formally self-dual even codes of length 22, M. Harada and P. R. J. Östergård, Graphs and Combinatorics 18 (2002), 507-516. (codes in digital form)
  60. Classifying optimal ternary codes of length 5 and covering radius 1, P. R. J. Östergård and W. D. Weakley, Beiträge zur Algebra und Geometrie 43 (2002), 445-449.
  61. More c-Bhaskar Rao designs with small block size, D. Deng, M. Greig, and P. R. J. Östergård, Discrete Mathematics 261 (2003), 189-208.
  62. Disproof of a conjecture on the existence of balanced optimal covering codes, P. R. J. Östergård, IEEE Transactions on Information Theory 49 (2003), 487-488.
  63. An improved upper bound for the football pool problem for nine matches, F. Di Pasquale and P. R. J. Östergård, Journal of Combinatorial Theory. Series A 102 (2003), 204-206.
  64. Optimal quaternary linear rate-1/2 codes of length ≤ 18, T. A. Gulliver, P. R. J. Östergård, and N. I. Senkevitch, IEEE Transactions on Information Theory 49 (2003), 1540-1543.
  65. On the covering radius of small codes, G. Kéri and P. R. J. Östergård, Studia Scientiarum Mathematicarum Hungarica 40 (2003), 243-256.
  66. Classification of whist tournaments with up to 12 players, H. Haanpää and P. R. J. Östergård, Discrete Applied Mathematics 129 (2003), 399-407.
  67. Binary two-error-correcting codes are better than quaternary, P. R. J. Östergård, Applicable Algebra in Engineering, Communication and Computing 14 (2003), 89-96.
  68. On the classification of self-dual codes over F5, M. Harada and P. R. J. Östergård, Graphs and Combinatorics 19 (2003), 203-214. (codes in digital form)
  69. Optimal linear rate 1/2 codes over F5 and F7, T. A. Gulliver, P. R. J. Östergård, and N. Senkevitch, Discrete Mathematics 265 (2003), 59-70. (codes in digital form)
  70. A covering problem for tori, P. R. J. Östergård and T. Riihonen, Annals of Combinatorics 7 (2003), 357-363.
  71. Classification of resolvable 2-(14,7,12) and 3-(14,7,5) designs, P. Kaski, L. B. Morales, P. R. J. Östergård, D. A. Rosenblueth, and C. Velarde, Journal of Combinatorial Mathematics and Combinatorial Computing 47 (2003), 65-74. (designs in digital form)
  72. Sets in Zn with distinct sums of pairs, H. Haanpää, A. Huima, and P. R. J. Östergård, Discrete Applied Mathematics 138 (2004), 99-106. (sets in digital form)
  73. Enumeration of balanced ternary designs, P. Kaski and P. R. J. Östergård, Discrete Applied Mathematics 138 (2004), 133-141. (designs in digital form)
  74. Miscellaneous classification results for 2-designs, P. Kaski and P. R. J. Östergård, Discrete Mathematics 280 (2004), 65-75.
  75. An updated table of binary/ternary mixed covering codes, R. Bertolo, P. R. J. Östergård, and W. D. Weakley, Journal of Combinatorial Designs 12 (2004), 157-176.
  76. The Steiner triple systems of order 19, P. Kaski and P. R. J. Östergård, Mathematics of Computation 73 (2004), 2075-2092.
  77. On the nonexistence of bent Hamiltonian paths in the grid graph P3 x P5 x P5, P. R. J. Östergård, Bulletin of the Institute of Combinatorics and its Applications 42 (2004), 87-88.
  78. There exist non-isomorphic STS(19) with equivalent point codes, P. Kaski and P. R. J. Östergård, Journal of Combinatorial Designs 12 (2004), 443-448.
  79. Binary optimal linear rate 1/2 codes, T. A. Gulliver and P. R. J. Östergård, Discrete Mathematics 283 (2004), 255-261. (codes in digital form)
  80. On a hypercube coloring problem, P. R. J. Östergård, Journal of Combinatorial Theory. Series A 108 (2004), 199-204.
  81. There exists no Hermitian self-dual quaternary [26,13,10]4 code, P. R. J. Östergård, IEEE Transactions on Information Theory 50 (2004), 3316-3317.
  82. Resolving the existence of full-rank tilings of binary Hamming spaces, P. R. J. Östergård and A. Vardy, SIAM Journal on Discrete Mathematics 18 (2004), 382-387.
  83. Constructing asymmetric covering codes by tabu search, P. R. J. Östergård and E. A. Seuranen, Journal of Combinatorial Mathematics and Combinatorial Computing 51 (2004), 165-173. (codes in digital form)
  84. One-factorizations of regular graphs of order 12, P. Kaski and P. R. J. Östergård, Electronic Journal of Combinatorics 12 (2005), #R2, 25pp.
  85. New results on codes with covering radius 1 and minimum distance 2, P. R. J. Östergård, J. Quistorff, and A. Wassermann, Designs, Codes and Cryptography 35 (2005), 241-250.
  86. Two new four-error-correcting binary codes, P. R. J. Östergård, Designs, Codes and Cryptography 36 (2005), 327-329.
  87. Bounds for covering codes over large alphabets, G. Kéri and P. R. J. Östergård, Designs, Codes and Cryptography 37 (2005), 45-60.
  88. A new bound for the zero-error capacity region of the two-user binary adder channel, M. Mattas and P. R. J. Östergård, IEEE Transactions on Information Theory 51 (2005), 3289-3291.
  89. Classification of self-orthogonal codes over F3 and F4, I. Bouyukliev and P. R. J. Östergård, SIAM Journal on Discrete Mathematics 19 (2005), 363-370.
  90. Near-extremal formally self-dual even codes of lengths 24 and 32, T. A. Gulliver, M. Harada, T. Nishimura, and P. R. J. Östergård, Designs, Codes and Cryptography 37 (2005), 465-471.
  91. Classification of directed and hybrid triple systems, P. R. J. Östergård and O. Pottonen, Bayreuther Mathematische Schriften 74 (2005), 276-291.
  92. Unidirectional covering codes, P. R. J. Östergård and E. A. Seuranen, IEEE Transactions on Information Theory 52 (2006), 336-340.
  93. New constructions of optimal self-dual binary codes of length 54, S. Bouyuklieva and P. R. J. Östergård, Designs, Codes and Cryptography 41 (2006), 101-109.
  94. The Steiner quadruple systems of order 16, P. Kaski, P. R. J. Östergård, and O. Pottonen, Journal of Combinatorial Theory. Series A 113 (2006), 1764-1770.
  95. The number of inequivalent (2R+3,7)R optimal covering codes, G. Kéri and P. R. J. Östergård, Journal of Integer Sequences 9 (2006), Article 06.4.7, 8pp.
  96. Classification of optimal binary self-orthogonal codes up to length 24, I. Bouyukliev, S. Bouyuklieva, T. A. Gulliver, and P. R. J. Östergård, Journal of Combinatorial Mathematics and Combinatorial Computing 59 (2006), 33-87.
  97. New lower bounds for asymmetric covering codes, E. A. Seuranen and P. R. J. Östergård, Congressus Numerantium 178 (2006), 57-63.
  98. Further results on the covering radius of small codes, G. Kéri and P. R. J. Östergård, Discrete Mathematics 307 (2007), 69-77.
  99. Sets in Abelian groups with distinct sums of pairs, H. Haanpää and P. R. J. Östergård, Journal of Number Theory 123 (2007), 144-153.
  100. Elementary p-groups with the Rédei property, P. R. J. Östergård and S. Szabó, International Journal of Algebra and Computation 17 (2007), 171-178.
  101. New uniquely decodable codes for the T-user binary adder channel with 3 ≤ T ≤ 5, L. Kiviluoto and P. R. J. Östergård, IEEE Transactions on Information Theory 53 (2007), 1219-1220.
  102. There exists no symmetric configuration with 33 points and line size 6, P. Kaski and P. R. J. Östergård, Australasian Journal of Combinatorics 38 (2007), 273-277.
  103. Algorithms for the combinatorial best barbeque problem, P. R. J. Östergård, V. Vaskelainen, and A. Mosig, MATCH. Communications in Mathematical and in Computer Chemistry 58 (2007), 309-321.
  104. There exist Steiner triple systems of order 15 that do not occur in a perfect binary one-error-correcting code, P. R. J. Östergård and O. Pottonen, Journal of Combinatorial Designs 15 (2007), 465-468.
  105. There are exactly five biplanes with k = 11, P. Kaski and P. R. J. Östergård, Journal of Combinatorial Designs 16 (2008), 117-127.
  106. Steiner triple systems of order 19 and 21 with subsystems of order 7, P. Kaski, P. R. J. Östergård, S. Topalova, and R. Zlatarski, Discrete Mathematics 308 (2008), 2732-2741.
  107. On the minimum size of binary codes with length 2R+4 and covering radius R, G. Kéri and P. R. J. Östergård, Designs, Codes and Cryptography 48 (2008), 165-169.
  108. Small p-groups with full-rank factorization, H. Haanpää, P. R. J. Östergård, and S. Szabó, International Journal of Algebra and Computation 18 (2008), 1019-1034.
  109. There exists no Steiner system S(4,5,17), P. R. J. Östergård and O. Pottonen, Journal of Combinatorial Theory. Series A 115 (2008), 1570-1573.
  110. There are 1,132,835,421,602,062,347 nonisomorphic one-factorizations of K14, P. Kaski and P. R. J. Östergård, Journal of Combinatorial Designs 17 (2009), 147-159.
  111. Classification of resolvable balanced incomplete block designs—The unitals on 28 points, P. Kaski and P. R. J. Östergård, Mathematica Slovaca 59 (2009), 121-136.
  112. Classification of the (0,2)-graphs of valency 8, A. E. Brouwer and P. R. J. Östergård, Discrete Mathematics 309 (2009), 532-547.
  113. Sperner capacity of small digraphs, L. Kiviluoto, P. R. J. Östergård, and V. P. Vaskelainen, Advances in Mathematics of Communications 3 (2009), 125-133.
  114. Reconstructing extended perfect binary one-error-correcting codes from their minimum distance graphs, I. Yu. Mogilnykh, P. R. J. Östergård, O. Pottonen, and F. I. Solov'eva, IEEE Transactions on Information Theory 55 (2009), 2622-2625.
  115. A catalogue of the Steiner triple systems of order 19, P. Kaski, P. R. J. Östergård, O. Pottonen, and L. Kiviluoto, Bulletin of the Institute of Combinatorics and its Applications 57 (2009), 35-41.
  116. The perfect binary one-error-correcting codes of length 15: Part I—Classification, P. R. J. Östergård and O. Pottonen, IEEE Transactions on Information Theory 55 (2009), 4657-4660.
  117. Linear codes with covering radius 3, A. A. Davydov and P. R. J. Östergård, Designs, Codes and Cryptography 54 (2010), 253-271.
  118. The nonexistence of a (K6-e)-decomposition of the complete graph K29, S. G. Hartke, P. R. J. Östergård, D. Bryant, and S. I. El-Zanati, Journal of Combinatorial Designs 18 (2010), 94-104.
  119. The perfect binary one-error-correcting codes of length 15: Part II—Properties, P. R. J. Östergård, O. Pottonen, and K. T. Phelps, IEEE Transactions on Information Theory 56 (2010), 2571-2582.
  120. Properties of the Steiner triple systems of order 19, C. J. Colbourn, A. D. Forbes, M. J. Grannell, T. S. Griggs, P. Kaski, P. R. J. Östergård, D. A. Pike, and O. Pottonen, Electronic Journal of Combinatorics 17 (2010), #R98, 30pp.
  121. Classification of binary constant weight codes, P. R. J. Östergård, IEEE Transactions on Information Theory 56 (2010), 3779-3785.
  122. A census of one-factorizations of the complete 3-uniform hypergraph of order 9, M. Khatirinejad and P. R. J. Östergård, Australasian Journal of Combinatorics 47 (2010), 239-245.
  123. A tournament of order 14 with disjoint Banks and Slater sets, P. R. J. Östergård and V. P. Vaskelainen, Discrete Applied Mathematics 158 (2010), 588-591.
  124. Classification of starters, V. Linja-aho and P. R. J. Östergård, Journal of Combinatorial Mathematics and Combinatorial Computing 75 (2010), 153-159.
  125. Nearly Kirkman triple systems of order 18 and Hanani triple systems of order 19, C. J. Colbourn, P. Kaski, P. R. J. Östergård, D. A. Pike, and O. Pottonen, Discrete Mathematics 311 (2011), 827-834.
  126. The number of Latin squares of order 11, A. Hulpke, P. Kaski, and P. R. J. Östergård, Mathematics of Computation 80 (2011), 1197-1219.
  127. Two optimal one-error-correcting codes of length 13 that are not doubly shortened perfect codes, P. R. J. Östergård and O. Pottonen, Designs, Codes and Cryptography 59 (2011), 281-285.
  128. Classification of difference matrices over cyclic groups, P. H. J. Lampio and P. R. J. Östergård, Journal of Statistical Planning and Inference 141 (2011), 1194-1207.
  129. The cycle switching graph of the Steiner triple systems of order 19 is connected, P. Kaski, V. Mäkinen, and P. R. J. Östergård, Graphs and Combinatorics 27 (2011), 539-546.
  130. Computing the domination number of grid graphs, S. Alanko, S. Crevals, A. Isopoussu, P. Östergård, and V. Pettersson, Electronic Journal of Combinatorics 18(1) (2011), #P141, 18pp.
  131. Russian doll search for the Steiner triple covering problem, P. R. J. Östergård and V. P. Vaskelainen, Optimization Letters 5 (2011), 631-638.
  132. On optimal binary one-error-correcting codes of lengths 2m-4 and 2m-3, D. S. Krotov, P. R. J. Östergård, and O. Pottonen, IEEE Transactions on Information Theory 57 (2011), 6771-6779.
  133. On the size of optimal three-error-correcting binary codes of length 16, P. R. J. Östergård, IEEE Transactions on Information Theory 57 (2011), 6824-6826.
  134. Switching codes and designs, P. R. J. Östergård, Discrete Mathematics 312 (2012), 621-632.
  135. Packing Costas arrays, J. H. Dinitz, P. R. J. Östergård, and D. R. Stinson, Journal of Combinatorial Mathematics and Combinatorial Computing 80 (2012), 385-403.
  136. Steiner triple systems satisfying the 4-vertex condition, P. Kaski, M. Khatirinejad, and P. R. J. Östergård, Designs, Codes and Cryptography 62 (2012), 323-330.
  137. On triple systems and strongly regular graphs, M. Behbahani, C. Lam, and P. R. J. Östergård, Journal of Combinatorial Theory. Series A 119 (2012), 1414-1426.
  138. The quaternary complex Hadamard matrices of orders 10, 12, and 14, P. H. J. Lampio, F. Szöllősi, and P. R. J. Östergård, Discrete Mathematics 313 (2013), 189-206.
  139. On the Shannon capacity of triangular graphs, K. A. Mathew, P. R. J. Östergård, and A. Popa, Electronic Journal of Combinatorics 20(2) (2013), #P27, 8pp.
  140. On optimal binary codes with unbalanced coordinates, P. R. J. Östergård, Applicable Algebra in Engineering, Communication and Computing 24 (2013), 197-200.
  141. Enumerating perfect matchings in n-cubes, P. R. J. Östergård and V. H. Pettersson, Order 30 (2013), 821-835.
  142. Enumerating cube tilings, K. A. Mathew, P. R. J. Östergård, and A. Popa, Discrete & Computational Geometry 50 (2013), 1112-1122.
  143. On the minimum size of 4-uniform hypergraphs without property B, P. R. J. Östergård, Discrete Applied Mathematics 163 (2014), 199-204.
  144. The Mendelsohn triple systems of order 13, M. Khatirinejad, P. R. J. Östergård, and A. Popa, Journal of Combinatorial Designs 22 (2014), 1-11.
  145. Counting Hamiltonian cycles in bipartite graphs, H. Haanpää and P. R. J. Östergård, Mathematics of Computation 83 (2014), 979-995.
  146. Large sets of t-designs over finite fields, M. Braun, A. Kohnert, P. R. J. Östergård, and A. Wassermann, Journal of Combinatorial Theory. Series A 124 (2014), 195-202.
  147. A note on Toeplitz' conjecture, V. H. Pettersson, H. A. Tverberg, and P. R. J. Östergård, Discrete & Computational Geometry 51 (2014), 722-728.
  148. Switching in one-factorisations of complete graphs, P. Kaski, A. de Souza Medeiros, P. R. J. Östergård, and I. M. Wanless, Electronic Journal of Combinatorics 21 (2014), #P2.49, 24pp.
  149. On the maximum length of coil-in-the-box codes in dimension 8, P. R. J. Östergård and V. H. Pettersson, Discrete Applied Mathematics 179 (2014), 193-200.
  150. Hypercube packings and their holes, K. A. Mathew and P. R. J. Östergård, Congressus Numerantium 219 (2014), 89-95.
  151. On hypercube packings, blocking sets and a covering problem, K. A. Mathew and P. R. J. Östergård, Information Processing Letters 115 (2015), 141-145.
  152. Exhaustive search for snake-in-the-box codes, P. R. J. Östergård and V. H. Pettersson, Graphs and Combinatorics 31 (2015), 1019-1028.
  153. Permutation codes invariant under isometries, I. Janiszczak, W. Lempken, P. R. J. Östergård, and R. Staszewski, Designs, Codes and Cryptography 75 (2015), 497-507.
  154. Independent domination of grids, S. Crevals and P. R. J. Östergård, Discrete Mathematics 338 (2015), 1379-1384.
  155. Bounds on the domination number of Kneser graphs, P. R. J. Östergård, Z. Shao, and X. Xu, Ars Mathematica Contemporanea 9 (2015), 197-205.
  156. Enumeration of Steiner triple systems with subsystems, P. Kaski, P. R. J. Östergård, and A. Popa, Mathematics of Computation 84 (2015), 3051-3067.
  157. Classification of Graeco-Latin cubes, J. I. Kokkala and P. R. J. Östergård, Journal of Combinatorial Designs 23 (2015), 509-521.
  158. On the classification of MDS codes, J. I. Kokkala, D. S. Krotov, and P. R. J. Östergård, IEEE Transactions on Information Theory 61 (2015), 6485-6492.
  159. Algorithms for finding maximum transitive subtournaments, L. Kiviluoto, P. R. J. Östergård, and V. P. Vaskelainen, Journal of Combinatorial Optimization 31 (2016), 802-814.
  160. Non-existence of a ternary constant weight (16,5,15;2048) diameter perfect code, D. S. Krotov, P. R. J. Östergård, and O. Pottonen, Advances in Mathematics of Communications 10 (2016), 393-399.
  161. Further results on the classification of MDS codes, J. I. Kokkala and P. R. J. Östergård, Advances in Mathematics of Communications 10 (2016), 489-498.
  162. Existence of q-analogs of Steiner systems, M. Braun, T. Etzion, P. R. J. Östergård, A. Vardy, and A. Wassermann, Forum of Mathematics. Pi 4 (2016), e7, 14pp.
  163. Planar hypohamiltonian graphs on 40 vertices, M. Jooyandeh, B. D. McKay, P. R. J. Östergård, V. H. Pettersson, and C. T. Zamfirescu, Journal of Graph Theory 84 (2017), 121-133.
  164. Classification of cyclic Steiner quadruple systems, Y. Chang, B. Fan, T. Feng, D. F. Holt, and P. R. J. Östergård, Journal of Combinatorial Designs 25 (2017), 103-121.
  165. Total domination of grid graphs, S. Crevals and P. R. J. Östergård, Journal of Combinatorial Mathematics and Combinatorial Computing 101 (2017), 175-192.
  166. New lower bounds for the Shannon capacity of odd cycles, K. A. Mathew and P. R. J. Östergård, Designs, Codes and Cryptography 84 (2017), 13-22.
  167. Constructing error-correcting binary codes using transitive permutation groups, A. Laaksonen and P. R. J. Östergård, Discrete Applied Mathematics 233 (2017), 65-70.
  168. Enumeration of Seidel matrices, F. Szöllősi and P. R. J. Östergård, European Journal of Combinatorics 69 (2018), 169-184.
  169. There is no McLaughlin geometry, P. R. J. Östergård and L. H. Soicher, Journal of Combinatorial Theory. Series A 155 (2018), 27-41.
  170. Switching of covering codes, P. R. J. Östergård and W. D. Weakley, Discrete Mathematics 341 (2018), 1778-1788.
  171. On the domination number of 2-dimensional torus graphs, S. Crevals and P. R. J. Östergård, Utilitas Mathematica 106 (2018), 289-300.
  172. New lower bounds for binary constant-dimension subspace codes, M. Braun, P. R. J. Östergård, and A. Wassermann, Experimental Mathematics 27 (2018), 179-183.
  173. The chromatic number of the square of the 8-cube, J. I. Kokkala and P. R. J. Östergård, Mathematics of Computation 87 (2018), 2551-2561.
  174. Mappings of Butson-type Hadamard matrices, P. R. J. Östergård and W. T. Paavola, Discrete Mathematics 341 (2018), 2387-2397.
  175. New results on tripod packings, P. R. J. Östergård and A. Pöllänen, Discrete & Computational Geometry 61 (2019), 271-284.
  176. The sextuply shortened binary Golay code is optimal, P. R. J. Östergård, Designs, Codes and Cryptography 87 (2019), 341-347.
  177. New lower bounds for q-ary error-correcting codes, A. Laaksonen and P. R. J. Östergård, Cryptography and Communications 11 (2019), 881-889.
  178. New lower bounds on binary constant weight error-correcting codes, M. Braun, J. Humpich, A. Laaksonen, and P. R. J. Östergård, Journal of Combinatorial Mathematics and Combinatorial Computing 111 (2019), 213-223.
  179. Orderly generation of Butson Hadamard matrices, P. H. J. Lampio, P. R. J. Östergård and F. Szöllősi, Mathematics of Computation 89 (2020), 313-331.
  180. On the structure of small strength-2 covering arrays, J. I. Kokkala, K. Meagher, R. Naserasr, K. J. Nurmela, P. R. J. Östergård, and B. Stevens, Journal of Combinatorial Designs 28 (2020), 5-24.
  181. Constructions of maximum few-distance sets in Euclidean spaces, F. Szöllősi and P. R. J. Östergård, Electronic Journal of Combinatorics 27 (2020), #P1.23, 18pp.
  182. Kirkman triple systems with subsystems, J. I. Kokkala and P. R. J. Östergård, Discrete Mathematics 343 (2020), 111960.
  183. Sparse Steiner triple systems of order 21, J. I. Kokkala and and P. R. J. Östergård, Journal of Combinatorial Designs 29 (2021), 75-83.
  184. Quaternary complex Hadamard matrices of order 18, P. R. J. Östergård and W. T. Paavola, Journal of Combinatorial Designs 29 (2021), 129-140.
  185. Algorithms and complexity for counting configurations in Steiner triple systems, D. Heinlein and P. R. J. Östergård, Journal of Combinatorial Designs 30 (2022), 527-546.
  186. Equivalence of Butson-type Hadamard matrices, P. R. J. Östergård, Journal of Algebraic Combinatorics 56 (2022), 271-277.
  187. Switching 3-edge-colorings of cubic graphs, J. Goedgebeur and P. R. J. Östergård, Discrete Mathematics 345 (2022), 112963.
  188. Enumerating Steiner triple systems, D. Heinlein and and P. R. J. Östergård, Journal of Combinatorial Designs 31 (2023), 479-495.
  189. Bussey systems and Steiner's tactical problem, C. J. Colbourn, D. L. Kreher, and P. R. J. Östergård, Glasnik Matematički. Serija III 58(78) (2023), 201-224.
  190. Steiner triple systems of order 21 with subsystems, D. Heinlein and and P. R. J. Östergård, Glasnik Matematički. Serija III 58(78) (2023), 233-245.

Chapters in books

  1. Code design, I. S. Honkala and P. R. J. Östergård, in: Local Search in Combinatorial Optimization, E. Aarts and J. K. Lenstra (Editors), Wiley, New York, 1997, pp. 441-456. Reprinted by Princeton University Press, Princeton, 2003.
  2. Constructing combinatorial objects via cliques, P. R. J. Östergård, in: Surveys in Combinatorics, 2005, B. S. Webb (Editor), Cambridge University Press, Cambridge, 2005, pp. 57-82.
  3. Computational methods in design theory, P. B. Gibbons and P. R. J. Östergård, in: Handbook of Combinatorial Designs, 2nd edition, C. J. Colbourn and J. H. Dinitz (Editors), Chapman & Hall/CRC Press, Boca Raton, 2007, pp. 755-783.
  4. Construction and classification of codes, P. R. J. Östergård, in: Concise Encyclopedia of Coding Theory, W. C. Huffman, J.-L. Kim, P. Solé (Editors), CRC Press, Boca Raton, 2021, pp. 61-77.

Conference papers

  1. On the verification of programmable logic controller programs, J. Lilius and P. Östergård, in: Proceedings of the Twelfth International Conference on Application and Theory of Petri Nets, Aarhus, 1991, pp. 310-328.
  2. Construction methods for mixed covering codes, P. R. J. Östergård, in: Analysis, Algebra, and Computers in Mathematical Research, M. Gyllenberg and L. E. Persson (Editors), Marcel Dekker, New York, 1994, pp. 387-408.
  3. On the 2-domatic number of binary Hamming spaces, P. R. J. Östergård, in: Proceedings of the II International Workshop on Optimal Codes and Related Topics, Sozopol, 1998, pp. 183-187.
  4. Optimal packings of equal circles in a square, K. J. Nurmela and P. R. J. Östergård, in: Combinatorics, Graph Theory, and Algorithms, Vol. II, Y. Alavi, D. R. Lick, and A. Schwenk (Editors), New Issues Press, Kalamazoo, 1999, pp. 671-680.
  5. On binary/ternary error-correcting codes with minimum distance 4, P. R. J. Östergård, in: Applied Algebra, Algebraic Algorithms and Error-Correcting Codes, M. Fossorier, H. Imai, S. Lin, and A. Poli (Editors), LNCS 1719, Springer, Berlin, 1999, pp. 472-481. (codes in digital form)
  6. Classification of MDS codes over small alphabets, J. I. Kokkola, D. S. Krotov, and P. R. J. Östergård, in: Coding Theory and Applications (4th Int'l Castle Meeting, Palmela Castle, Portugal, September 15-18, 2014), R. Pinto, P. Rocha Malonek, and P. Vettori (Editors), CIM Series in Mathematical Sciences 3, Springer, Cham, Switzerland, 2015, pp. 227-235.
  7. LCL problems on grids, S. Brandt, J. Hirvonen, J. H. Korhonen, T. Lempiäinen, P. R. J. Östergård, C. Purcell, J. Rybicki, J. Suomela, and P. Uznański, in: PODC'17, Proceedings of the ACM Symposium on Principles of Distributed Computing (Washington, DC, USA, July 25-27, 2017), E. M. Schiller and A. A. Schwarzmann (Editors), ACM Press, New York, 2017, pp. 101-110.
  8. New lower bounds on error-correcting ternary, quaternary and quinary codes, A. Laaksonen and P. R. J. Östergård, in: Coding Theory and Applications (5th Int'l Castle Meeting, Vihula, Estonia, August 28-31, 2017), Á. I. Barbero, V. Skachek, and Ø. Ytrehus (Editors), LNCS 10495, Springer, Cham, Switzerland, 2017, pp. 228-237.
  9. Pushing the limits of computational combinatorial constructions, L. Moura, A. Nakic, P. Östergård, A. Wassermann, and C. Weiß (Editors), in: Dagstuhl Reports 13, no. 4, 2023, pp. 40-57.
  10. Constructing random Steiner triple systems: An experimental study, D. Heinlein and P. R. J. Östergård, in: New Advances in Designs, Codes and Cryptography (Stinson66, Toronto, Canada, June 13-17, 2022), C. J. Colbourn and J. H. Dinitz (Editors), Fields Institute Communications 86, Springer, Cham, Switzerland, 2024, pp. 155-176.

Thesis

  1. Construction methods for covering codes, P. R. J. Östergård, Ph.D. dissertation, Digital Systems Laboratory, Helsinki University of Technology, Espoo, Research Report A25, 1993. (abstract)

Datasets

  1. Enumerating cube tilings, A. Mathew, P. Östergård and A. Popa, Zenodo, https://doi.org/10.5281/zenodo.7121154 (September 28, 2013).
  2. Dataset for New results on tripod packings, P. R. J. Östergård and A. Pöllänen, Zenodo, https://doi.org/10.5281/zenodo.1230275 (April 26, 2018).
  3. Classification of small strength-2 covering arrays, J. I. Kokkala, K. Meagher, R. Naserasr, K. J. Nurmela, P. R. J. Östergård, and B. Stevens, Zenodo, https://doi.org/10.5281/zenodo.1476058 (October 31, 2018).
  4. Dataset for Orderly generation of Butson Hadamard matrices, P. H. J. Lampio, P. R. J. Östergård and F. Szöllősi, Zenodo, https://doi.org/10.5281/zenodo.2585765 (March 13, 2019)
  5. Kirkman triple systems with subsystems, J. I. Kokkala and P. R. J. Östergård, Zenodo, https://doi.org/10.5281/zenodo.2650509 (August 29, 2019).
  6. Dataset for Quaternary complex Hadamard matrices of order 18, P. R. J. Östergård and W. T. Paavola, Zenodo, https://doi.org/10.5281/zenodo.3733060 (March 30, 2020).
  7. Sparse Steiner triple systems of order 21, J. I. Kokkala and P. R. J. Östergård, Zenodo, https://doi.org/10.5281/zenodo.3899950 (June 18, 2020).
  8. Dataset and code for Switching 3-edge-colorings of cubic graphs, J. Goedgebeur and P. R. J. Östergård, Zenodo, https://doi.org/10.5281/zenodo.6386911 (April 21, 2021).
  9. Dataset for Algorithms and complexity for counting configurations in Steiner triple systems, D. Heinlein and P. R. J. Östergård, Zenodo, https://doi.org/10.5281/zenodo.5519800 (September 22, 2021).

Patents

  1. Väylin laajennettu TST-arkkitehtuuri (Bus extended TST-architecture), O. Strandberg and P. Östergård, Finnish Patent No. FI96373, 10.6.1996. Also UK Patent No. GB2303522.
  2. SDH-signaalien kytkeminen TS'S'TS'S'T-kytkentäverkossa (Coupling of SDH signals in a TS'S'TS'S'T coupling network), T. Kasurinen and P. Östergård, Finnish Patent No. FI97600, 10.1.1997. Also International Patent No. WO9532598.

Computer programs

  1. Cliquer [C program], S. Niskanen and P. R. J. Östergård, available at http://users.aalto.fi/~pat/cliquer.html.

Reports and miscellaneous papers

  1. Constructions of mixed covering codes, P. R. J. Östergård, Digital Systems Laboratory, Helsinki University of Technology, Espoo, Research Report A18, 1991. (abstract)
  2. Constructing covering designs by simulated annealing, K. J. Nurmela and P. R. J. Östergård, Digital Systems Laboratory, Helsinki University of Technology, Espoo, Technical Report B10, 1993. (abstract) ( a C program)
  3. New upper bounds for binary/ternary mixed covering codes, P. R. J. Östergård and H. O. Hämäläinen, Digital Systems Laboratory, Helsinki University of Technology, Espoo, Research Report A22, 1993. ( abstract)
  4. Om approximativa lösningar till kombinatoriska optimeringsproblem (On approximate solutions of combinatorial optimization problems), P. Östergård, Elementa 78 (1995), 17-19.
  5. Matemaatikon kaljakori kilisee (The beer crate of a mathematician is clinking), K. Nurmela and P. Östergård, Helsingin Sanomat, 17 June 1995, p. D2.
  6. Greedy and heuristic algorithms for codes and colorings, T. Etzion and P. R. J. Östergård, Computer Science Department, Technion, Haifa, Technical Report CS 909, 1997.
  7. Bounds on mixed binary/ternary codes, A. E. Brouwer, H. O. Hämäläinen, P. R. J. Östergård, and N. J. A. Sloane, AT&T Labs Research, Florham Park, Technical Report 97.14.1, 1997.
  8. Ett cirkelpackningsproblem—eller: Hur man får flaskorna att rymmas i korgen (A circle packing problem—or: How to fit the bottles in the basket), P. R. J. Östergård and K. J. Nurmela, Normat 46 (1998), 64-70.
  9. Covering a square with up to 30 equal circles, K. J. Nurmela and P. R. J. Östergård, Laboratory for Theoretical Computer Science, Helsinki University of Technology, Espoo, Research Report A62, 2000. (abstract)
  10. On the covering radius of small codes, G. Kéri and P. R. J. Östergård, Laboratory of Operations Research and Decision Systems, Computer and Automation Institute, Hungarian Academy of Sciences, Budapest, Report WP 2003-1, 2003.
  11. Bounds for covering codes over large alphabets, G. Kéri and P. R. J. Östergård, Laboratory of Operations Research and Decision Systems, Computer and Automation Institute, Hungarian Academy of Sciences, Budapest, Reports WP 2003-2 and WP 2004-4, 2003/2004.
  12. Cliquer user's guide, version 1.0, S. Niskanen and P. R. J. Östergård, Communications Laboratory, Helsinki University of Technology, Espoo, Technical Report T48, 2003.
  13. Further results on the covering radius of small codes, G. Kéri and P. R. J. Östergård, Laboratory of Operations Research and Decision Systems, Computer and Automation Institute, Hungarian Academy of Sciences, Budapest, Reports WP 2003-7 and WP 2004-1, 2003/2004.
  14. A census of small Petri nets, P. R. J. Östergård, Petri Net Newsletter 64 (2003), 7-14.
  15. Sets in Abelian groups with distinct sums of pairs, H. Haanpää and P. R. J. Östergård, Laboratory for Theoretical Computer Science, Helsinki University of Technology, Espoo, Research Report A87, 2004. (abstract)
  16. Steinerin kolmikkosysteemeistä sudokuun (From Steiner triple systems to sudoku), H. Haanpää and P. R. J. Östergård, Arkhimedes no. 2, 2006, 19-21.
  17. Book review "P. G. Szabó, M. C. Markót, T. Csendes, E. Specht, L. G. Casado, and I. García, New Approaches to Circle Packing in a Square, Springer, Berlin, 2007", P. R. J. Östergård, Operations Research Letters 36 (2008), 277-278.
  18. The perfect binary one-error-correcting codes of length 15: Part II—Properties, P. R. J. Östergård, O. Pottonen, and K. T. Phelps, Department of Communications and Networking, Helsinki University of Technology, Espoo, Report 2/2009, 2009.
  19. Algorithms for finding maximum transitive subtournaments, L. Kiviluoto, P. R. J. Östergård, and V. P. Vaskelainen, Department of Communications and Networking, Aalto University, Espoo, Report 5/2010, 2010.
  20. Om q-analogier (On q-analogs), P. R. J. Östergård, Arkhimedes no. 3, 2014, 16-19.
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Latest update: April 15, 2024.