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A215865 Number of simple labeled graphs on n+5 nodes with exactly n connected components that are trees or cycles. 2
0, 1356, 15029, 90734, 394506, 1381695, 4138827, 11002068, 26603148, 59546487, 124984860, 248436188, 471271892, 858408642, 1508851218, 2569865520, 4255708464, 6872006526, 10847057991, 16771536474, 25448295950, 37954221305, 55716334245, 80604653220 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..1000

FORMULA

G.f.: (194*x^4-713*x^3-5*x^2+113*x+1356)*x/(1-x)^11.

a(n) = C(n+5,6)*(3*n^4+130*n^3+1565*n^2+7006*n+12992)/16.

MAPLE

a:= n-> binomial(n+5, 6)*(12992+(7006+(1565+(130+3*n)*n)*n)*n)/16:

seq(a(n), n=0..40);

CROSSREFS

A diagonal of A215861.

Sequence in context: A107559 A056103 A259249 * A172379 A192319 A125270

Adjacent sequences:  A215862 A215863 A215864 * A215866 A215867 A215868

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Aug 25 2012

STATUS

approved

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Last modified April 10 01:28 EDT 2020. Contains 333392 sequences. (Running on oeis4.)