This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A326343 #11 Aug 21 2019 02:26:04 %S A326343 1,2,6,42,894,62350 %N A326343 Number of inequivalent n X n binary matrices with total support, where equivalence means permutations of rows or columns. %C A326343 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 A326343 Number of inequivalent 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 A326343 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 A326343 Christian Stricker, <a href="/A326343/a326343.txt">All such matrices for n = 3</a> %H A326343 Christian Stricker, <a href="/A326343/a326343_1.txt">All such matrices for n = 4</a> %H A326343 Christian Stricker, <a href="/A326343/a326343_2.txt">All such matrices for n = 5</a> %e A326343 For n = 2 the a(2) = 2 matrices are: %e A326343 [1 1] [1 0] %e A326343 [1 1], [0 1]. %Y A326343 A326342 additionally considers equivalent matrices. %K A326343 nonn,more %O A326343 1,2 %A A326343 _Christian Stricker_, Jun 28 2019