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A215767 Number of undirected labeled graphs on n nodes with exactly 7 cycle graphs as connected components. 2
1, 28, 462, 6300, 82929, 1128204, 16187314, 245722477, 3944372432, 66863837040, 1194908786890, 22468992674310, 443708326841383, 9184432111987960, 198909290886899005, 4499373643453767540, 106128250525908452226, 2606280798870785902866, 66541442123879872392375 (list; graph; refs; listen; history; text; internal format)
OFFSET

7,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 7..170

MAPLE

T:= proc(n, k) option remember; `if`(k<0 or k>n, 0, `if`(n=0, 1,

      add(binomial(n-1, i)*T(n-1-i, k-1)*ceil(i!/2), i=0..n-k)))

    end:

a:= n-> T(n, 7):

seq (a(n), n=7..25);

CROSSREFS

Column k=7 of A215771.

Sequence in context: A022752 A000771 A327508 * A079518 A320820 A160060

Adjacent sequences:  A215764 A215765 A215766 * A215768 A215769 A215770

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Aug 23 2012

STATUS

approved

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Last modified March 3 03:03 EST 2021. Contains 341756 sequences. (Running on oeis4.)