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A215865
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Number of simple labeled graphs on n+5 nodes with exactly n connected components that are trees or cycles.
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2
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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)
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OFFSET
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0,2
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LINKS
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FORMULA
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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.
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MAPLE
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a:= n-> binomial(n+5, 6)*(12992+(7006+(1565+(130+3*n)*n)*n)*n)/16:
seq(a(n), n=0..40);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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