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A218375 Number of simple labeled graphs on n nodes with an odd number of components. 3
0, 1, 1, 5, 44, 784, 27544, 1887320, 252478976, 66372782656, 34508641142656, 35645444718410240, 73356919713975202304, 301275013344908538586624, 2471655525947208345490898944, 40527712672440838261073708426240, 1328579255442486951291268858109935616 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
LINKS
FORMULA
E.g.f.: sinh(A(x)-1) where A(x) is the e.g.f. for A001187.
MATHEMATICA
nn=16; a=Sum[2^Binomial[n, 2]x^n/n!, {n, 0, nn}]; Range[0, nn]!CoefficientList[Series[Sinh[ Log[a]], {x, 0, nn}], x]
CROSSREFS
Cf. A218374.
Sequence in context: A229396 A301655 A048940 * A360988 A058792 A113948
KEYWORD
nonn
AUTHOR
Geoffrey Critzer, Oct 27 2012
STATUS
approved

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Last modified May 29 14:43 EDT 2024. Contains 372952 sequences. (Running on oeis4.)