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%I #26 Feb 25 2020 08:14:09
%S 1,1,2,7,28,134,729,4408,29256,210710,1633107,13528646,119117240,
%T 1109528752,10889570768,112226155225,1210829041710,13640416024410,
%U 160069458445202,1952602490538038,24712910192430620,323964329622503527,4391974577299578248,61488854148194151940
%N Number of zero-one matrices with n ones and no zero rows or columns and with distinct rows, up to permutation of rows.
%C Also the number of labeled hypergraphs spanning an initial interval of positive integers with edge-sizes summing to n. - _Gus Wiseman_, Dec 18 2018
%H Alois P. Heinz, <a href="/A116539/b116539.txt">Table of n, a(n) for n = 0..300</a>
%H P. J. Cameron, T. Prellberg and D. Stark, <a href="https://arxiv.org/abs/math/0510155">Asymptotics for incidence matrix classes </a>, arXiv:math/0510155 [math.CO], 2005-2006.
%H M. Klazar, <a href="https://arxiv.org/abs/math/0305048">Extremal problems for ordered hypergraphs</a>, arXiv:math/0305048 [math.CO], 2003.
%e From _Gus Wiseman_, Dec 18 2018: (Start)
%e The a(3) = 7 edge-sets:
%e {{1,2,3}}
%e {{1},{1,2}}
%e {{2},{1,2}}
%e {{1},{2,3}}
%e {{2},{1,3}}
%e {{3},{1,2}}
%e {{1},{2},{3}}
%e Inequivalent representatives of the a(4) = 28 0-1 matrices:
%e [1111]
%e .
%e [100][1000][010][0100][001][0010][0001][110][110][1100][101][1010][1001]
%e [111][0111][111][1011][111][1101][1110][101][011][0011][011][0101][0110]
%e .
%e [10][100][100][1000][100][100][1000][1000][010][010][0100][0100][0010]
%e [01][010][010][0100][001][001][0010][0001][001][001][0010][0001][0001]
%e [11][101][011][0011][110][011][0101][0110][110][101][1001][1010][1100]
%e .
%e [1000]
%e [0100]
%e [0010]
%e [0001]
%e (End)
%p b:= proc(n, i, k) b(n, i, k):=`if`(n=0, 1, `if`(i<1, 0, add(b(n-i*j,
%p min(n-i*j, i-1), k)*binomial(binomial(k, i), j), j=0..n/i)))
%p end:
%p a:= n-> add(add(b(n$2, i)*(-1)^(k-i)*binomial(k, i), i=0..k), k=0..n):
%p seq(a(n), n=0..23); # _Alois P. Heinz_, Sep 13 2019
%t b[n_, i_, k_] := b[n, i, k] = If[n == 0, 1, If[i < 1, 0, Sum[b[n - i*j, Min[n - i*j, i - 1], k]*Binomial[Binomial[k, i], j], {j, 0, n/i}]]];
%t a[n_] := Sum[Sum[b[n, n, i]*(-1)^(k-i)*Binomial[k, i], {i, 0, k}], {k, 0, n}];
%t a /@ Range[0, 23] (* _Jean-François Alcover_, Feb 25 2020, after _Alois P. Heinz_ *)
%Y Binary matrices with distinct rows and columns, various versions: A059202, A088309, A088310, A088616, A089673, A089674, A093466, A094000, A094223, A116532, A116539, A181230, A259763
%Y Cf. A049311, A058891, A101370, A255906, A283877, A306021, A319190.
%Y Row sums of A326914 and of A326962.
%K nonn
%O 0,3
%A _Vladeta Jovovic_, Mar 27 2006
%E a(0)=1 prepended and more terms added by _Alois P. Heinz_, Sep 13 2019
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