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%I #6 Nov 07 2019 21:08:28
%S 1,0,1,6,29,510,5032,161406,3294405,194342910,7934652356,881008805886,
%T 71275547085536,15178191426486270,2434250064518832302,
%U 1008694542117649154046,321680912414994434144165,262063364967549826752315390,166681427053102507699172431372
%N Number of labeled bipartite graphs on n vertices with no isolated vertices.
%H Andrew Howroyd, <a href="/A122802/b122802.txt">Table of n, a(n) for n = 0..50</a>
%F a(2n+1) = A052332(2n+1); a(2n) = A052332(2n) - A122801(n) for n > 0.
%o (PARI) a(n)={sum(k=0, n, binomial(n, k)*(2^k-2)^(n-k)) - if(n%2==0&&n>0, binomial(n-1, n/2)*sum(k=0, n/2, binomial(n/2, k)*(-1)^k*(2^(n/2-k)-1)^(n/2)))} \\ _Andrew Howroyd_, Nov 07 2019
%Y Cf. A122801, A052332, A001831, A002031, A047863.
%K nonn
%O 0,4
%A _Max Alekseyev_, Sep 11 2006
%E Terms a(17) and beyond from _Andrew Howroyd_, Nov 07 2019
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