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%I #17 Aug 21 2019 02:25:44
%S 1,3,49,7443,6092721
%N Number of n X n binary matrices with total support.
%C A nonnegative matrix has total support if it is nonzero and for every positive entry there exists a permutation of the columns such that the positive entry is a diagonal entry afterwards and all diagonal entries are positive afterwards.
%C Number of n X n binary matrices generated by applying the sign function on the entries of a doubly stochastic n X n matrix. - [R. Sinkhorn and P. Knopp (1967)]
%H R. Sinkhorn and P. Knopp, <a href="https://projecteuclid.org/euclid.pjm/1102992505">Concerning nonnegative matrices and doubly stochastic matrices</a>, Pacific Journal of Mathematics, 21(2):343-348, 1967.
%H Christian Stricker, <a href="/A326342/a326342.txt">All such matrices for n = 3</a>
%H Christian Stricker, <a href="/A326342/a326342_1.txt">All such matrices for n = 4</a>
%e For n = 2 the a(2) = 3 matrices are:
%e [1 1] [1 0] [0 1]
%e [1 1], [0 1], [1 0].
%Y A326343 counts only the inequivalent matrices.
%K nonn,more
%O 1,2
%A _Christian Stricker_, Jun 28 2019
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