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 A054976 Number of binary n X n matrices with no zero rows or columns, up to row and column permutation. 19
 1, 3, 17, 179, 3835, 200082, 29610804, 13702979132, 20677458750966, 103609939177198046, 1745061194503344181714, 99860890306900024150675406, 19611238933283757244479826044874, 13340750149227624084760722122669739026, 31706433098827528779057124372265863803044450 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Also the number of non-isomorphic set multipartitions (multisets of sets) with n parts and n vertices. - Gus Wiseman, Nov 18 2018 LINKS Andrew Howroyd, Table of n, a(n) for n = 1..50 FORMULA a(n) = A002724(n) - 2*A002725(n-1) + A002724(n-1). EXAMPLE From Gus Wiseman, Nov 18 2018: (Start) Inequivalent representatives of the a(3) = 17 matrices: 100 100 100 100 100 010 010 001 001 001 001 110 101 101 011 011 111 100 010 001 011 011 001 101 001 101 011 111 101 011 011 011 111 111 011 001 011 011 111 111 011 111 011 111 111 011 011 111 111 111 111 Non-isomorphic representatives of the a(1) = 1 through a(3) = 17 set multipartitions: {{1}} {{1},{2}} {{1},{2},{3}} {{2},{1,2}} {{1},{1},{2,3}} {{1,2},{1,2}} {{1},{3},{2,3}} {{1},{2,3},{2,3}} {{2},{1,3},{2,3}} {{2},{3},{1,2,3}} {{3},{1,3},{2,3}} {{3},{3},{1,2,3}} {{1,2},{1,3},{2,3}} {{1},{2,3},{1,2,3}} {{1,3},{2,3},{2,3}} {{3},{2,3},{1,2,3}} {{1,3},{2,3},{1,2,3}} {{2,3},{2,3},{1,2,3}} {{3},{1,2,3},{1,2,3}} {{2,3},{1,2,3},{1,2,3}} {{1,2,3},{1,2,3},{1,2,3}} (End) MATHEMATICA A002724 = Cases[Import["https://oeis.org/A002724/b002724.txt", "Table"], {_, _}][[All, 2]]; A002725 = Cases[Import["https://oeis.org/A002725/b002725.txt", "Table"], {_, _}][[All, 2]]; a[n_] := A002724[[n + 1]] - 2 A002725[[n]] + A002724[[n]]; a /@ Range[1, 13] (* Jean-François Alcover, Sep 14 2019 *) CROSSREFS Column sums of A057150. Cf. A007716, A048291 (labeled), A049311, A057149, A057151, A104601, A104602, A319616, A320808. Sequence in context: A053934 A159592 A126443 * A304863 A163886 A340881 Adjacent sequences: A054973 A054974 A054975 * A054977 A054978 A054979 KEYWORD easy,nonn AUTHOR Vladeta Jovovic, May 27 2000 EXTENSIONS More terms from David Wasserman, Mar 06 2002 Terms a(14) and beyond from Andrew Howroyd, Apr 11 2020 STATUS approved

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Last modified August 12 16:47 EDT 2024. Contains 375113 sequences. (Running on oeis4.)