A057150 Triangle read by rows: T(n,k) = number of k X k binary matrices with n ones, with no zero rows or columns, up to row and column permutation.
1, 0, 1, 0, 1, 1, 0, 1, 2, 1, 0, 0, 5, 2, 1, 0, 0, 4, 11, 2, 1, 0, 0, 3, 21, 14, 2, 1, 0, 0, 1, 34, 49, 15, 2, 1, 0, 0, 1, 33, 131, 69, 15, 2, 1, 0, 0, 0, 33, 248, 288, 79, 15, 2, 1, 0, 0, 0, 19, 410, 840, 420, 82, 15, 2, 1, 0, 0, 0, 14, 531, 2144, 1744, 497, 83, 15, 2, 1
Offset: 1
Examples
[1], [0,1], [0,1,1], [0,1,2,1], [0,0,5,2,1], [0,0,4,11,2,1], ...; There are 8 square binary matrices with 5 ones, with no zero rows or columns, up to row and column permutation: 5 of size 3 X 3: [0 0 1] [0 0 1] [0 0 1] [0 0 1] [0 0 1] [0 0 1] [0 1 0] [0 1 1] [0 1 1] [1 1 0] [1 1 1] [1 1 1] [1 0 1] [1 1 0] [1 1 0] 2 of size 4 X 4: [0 0 0 1] [0 0 0 1] [0 0 0 1] [0 0 1 0] [0 0 1 0] [0 1 0 0] [1 1 0 0] [1 0 0 1] and 1 of size 5 X 5: [0 0 0 0 1] [0 0 0 1 0] [0 0 1 0 0] [0 1 0 0 0] [1 0 0 0 0]. From _Gus Wiseman_, Nov 14 2018: (Start) Triangle begins: 1 0 1 0 1 1 0 1 2 1 0 0 5 2 1 0 0 4 11 2 1 0 0 3 21 14 2 1 0 0 1 34 49 15 2 1 0 0 1 33 131 69 15 2 1 0 0 0 33 248 288 79 15 2 1 Non-isomorphic representatives of the multiset partitions counted in row 6 {0,0,4,11,2,1} are: {{12}{13}{23}} {{1}{1}{1}{234}} {{1}{2}{3}{3}{45}} {{1}{2}{3}{4}{5}{6}} {{1}{23}{123}} {{1}{1}{24}{34}} {{1}{2}{3}{5}{45}} {{13}{23}{23}} {{1}{1}{4}{234}} {{3}{23}{123}} {{1}{2}{34}{34}} {{1}{3}{24}{34}} {{1}{3}{4}{234}} {{1}{4}{24}{34}} {{1}{4}{4}{234}} {{2}{4}{12}{34}} {{3}{4}{12}{34}} {{4}{4}{12}{34}} (End)
Crossrefs
Programs
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Mathematica
permcount[v_List] := Module[{m = 1, s = 0, k = 0, t}, For[i = 1, i <= Length[v], i++, t = v[[i]]; k = If[i > 1 && t == v[[i - 1]], k + 1, 1]; m *= t*k; s += t]; s!/m]; c[p_List, q_List, k_] := SeriesCoefficient[Product[Product[(1 + O[x]^(k + 1) + x^LCM[p[[i]], q[[j]]])^GCD[p[[i]], q[[j]]], {j, 1, Length[q]}], {i, 1, Length[p]}], {x, 0, k}]; M[m_, n_, k_] := M[m, n, k] = Module[{s = 0}, Do[Do[s += permcount[p]* permcount[q]*c[p, q, k], {q, IntegerPartitions[n]}], {p, IntegerPartitions[m]}]; s/(m!*n!)]; T[n_, k_] := M[k, k, n] - 2*M[k, k - 1, n] + M[k - 1, k - 1, n]; Table[T[n, k], {n, 1, 12}, {k, 1, n}] // Flatten (* Jean-François Alcover, Sep 10 2019, after Andrew Howroyd *)
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PARI
\\ See A321609 for M. T(n,k) = M(k,k,n) - 2*M(k,k-1,n) + M(k-1,k-1,n); \\ Andrew Howroyd, Nov 14 2018
Extensions
Duplicate seventh row removed by Gus Wiseman, Nov 14 2018
Comments