A052833 Expansion of e.g.f.: (log(2-exp(x)))^2.

0, 0, 2, 12, 72, 500, 4080, 38668, 419160, 5124708, 69831360, 1049972924, 17273719848, 308714206996, 5956836347280, 123437573728620, 2734197673727736, 64473939310567364, 1612626113517932640, 42645398700110627356, 1188880256538133537224, 34849264499702702749812

Offset

0,3

Comments

Previous name was: A simple grammar.

Links

G. C. Greubel, Table of n, a(n) for n = 0..424

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 799

Formula

E.g.f.: log(-1/(-2+exp(x)))^2.

a(n) ~ (n-1)! * 2*(log(n) + gamma - log(2) - log(log(2)))/log(2)^n, where gamma is Euler-Mascheroni constant (A001620). - Vaclav Kotesovec, Sep 30 2013

Maple

spec := [S, {B=Set(Z, 1 <= card), C=Cycle(B), S=Prod(C, C)}, labeled]: seq(combstruct[count](spec, size=n), n=0..20);

Mathematica

CoefficientList[Series[Log[2-E^x]^2, {x, 0, 20}], x]* Range[0, 20]! (* Vaclav Kotesovec, Sep 30 2013 *)

Prog

(PARI) x='x+O('x^30); concat([0, 0], Vec(serlaplace((log(2-exp(x)))^2))) \\ G. C. Greubel, Sep 05 2018

Crossrefs

Sequence in context: A181966 A052556 A371039 * A277490 A296975 A144086

Adjacent sequences: A052830 A052831 A052832 * A052834 A052835 A052836

Keyword

easy,nonn

Author

encyclopedia(AT)pommard.inria.fr, Jan 25 2000

Extensions

New name, using e.g.f., by Vaclav Kotesovec, Sep 30 2013

More terms from Alois P. Heinz, Mar 16 2016

Status

approved