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A215860 Number of simple labeled graphs on n nodes with exactly 10 connected components that are trees or cycles. 3
1, 55, 2365, 90805, 3367364, 124984860, 4743643190, 186488038880, 7653850266777, 329429479792985, 14903545528332565, 709243144460040645, 35495878932860944422, 1866637759375098988740, 103014318586612720480259, 5957391569989223921495400 (list; graph; refs; listen; history; text; internal format)
OFFSET

10,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 10..150

EXAMPLE

a(11) = 55: each graph has one 2-node tree and 9 1-node trees and C(11,2) = 55.

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)*

      `if`(i<2, 1, i!/2 +(i+1)^(i-1)), i=0..n-k)))

    end:

a:= n-> T(n, 10):

seq(a(n), n=10..30);

CROSSREFS

Column k=10 of A215861.

The unlabeled version is A215980.

Sequence in context: A240687 A053113 A012048 * A020536 A212788 A131557

Adjacent sequences:  A215857 A215858 A215859 * A215861 A215862 A215863

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Aug 26 2012

STATUS

approved

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Last modified April 3 18:40 EDT 2020. Contains 333198 sequences. (Running on oeis4.)