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%I #12 Jun 25 2023 08:13:31
%S 1,1,2,13,150,3529,194203,29350896,13668966399,20662731749804,
%T 103588456044907944,1744955436868541083098,99859125842603176324368784,
%U 19611138475504485904873456937288,13340730475029359536419515017040194246,31706419735128559894860278029259121951682970,265351742295121848168241791689670791068746978140331
%N Number of connected bipartite graphs on 2n nodes with a marked bipartite set of size n.
%C Also, number of n X n binary matrices up to permutations of rows and columns, representing the reduced adjacency matrices of connected bipartite graphs (cf. A002724).
%H Max Alekseyev, <a href="/A363846/b363846.txt">Table of n, a(n) for n = 0..50</a>
%F a(n) = A363845(2n, n).
%Y Diagonal of the rectangular array described in A363845.
%Y Cf. A002724, A028657, A123549.
%K nonn
%O 0,3
%A _Max Alekseyev_, Jun 24 2023