A218375 Number of simple labeled graphs on n nodes with an odd number of components.

0, 1, 1, 5, 44, 784, 27544, 1887320, 252478976, 66372782656, 34508641142656, 35645444718410240, 73356919713975202304, 301275013344908538586624, 2471655525947208345490898944, 40527712672440838261073708426240, 1328579255442486951291268858109935616

Offset

0,4

Links

Alois P. Heinz, Table of n, a(n) for n = 0..50

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 A374583

Adjacent sequences: A218372 A218373 A218374 * A218376 A218377 A218378

Keyword

nonn

Author

Geoffrey Critzer, Oct 27 2012

Status

approved