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%I #5 Aug 23 2012 21:06:16
%S 1,15,140,1190,10857,109935,1222210,14771955,192855949,2705536834,
%T 40597839100,648954464340,11010645610113,197646020548569,
%U 3742573587799761,74560940574685875,1559079985774886316,34142131775027937276,781462189858194371736
%N Number of undirected labeled graphs on n nodes with exactly 5 cycle graphs as connected components.
%H Alois P. Heinz, <a href="/A215765/b215765.txt">Table of n, a(n) for n = 5..170</a>
%p T:= proc(n, k) option remember; `if`(k<0 or k>n, 0, `if`(n=0, 1,
%p add(binomial(n-1, i)*T(n-1-i, k-1)*ceil(i!/2), i=0..n-k)))
%p end:
%p a:= n-> T(n, 5):
%p seq (a(n), n=5..25);
%Y Column k=5 of A215771.
%K nonn
%O 5,2
%A _Alois P. Heinz_, Aug 23 2012
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