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 A326342 Number of n X n binary matrices with total support. 2
 1, 3, 49, 7443, 6092721 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS 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. 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)] LINKS Table of n, a(n) for n=1..5. R. Sinkhorn and P. Knopp, Concerning nonnegative matrices and doubly stochastic matrices, Pacific Journal of Mathematics, 21(2):343-348, 1967. Christian Stricker, All such matrices for n = 3 Christian Stricker, All such matrices for n = 4 EXAMPLE For n = 2 the a(2) = 3 matrices are: [1 1] [1 0] [0 1] [1 1], [0 1], [1 0]. CROSSREFS A326343 counts only the inequivalent matrices. Sequence in context: A203743 A086459 A180602 * A203700 A063893 A291707 Adjacent sequences: A326339 A326340 A326341 * A326343 A326344 A326345 KEYWORD nonn,more AUTHOR Christian Stricker, Jun 28 2019 STATUS approved

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Last modified August 4 01:30 EDT 2024. Contains 374905 sequences. (Running on oeis4.)