A185161 G.f. = 1/(1-g(x)) where g(x) is the g.f. for A141309.

1, 2, 7, 36, 283, 2898, 36169, 524976, 8659186, 159736316, 3257811334, 72797444280, 1769125982092, 46466434382032, 1311960028913384, 39633438764146568, 1275742281105759813, 43593785716301112538, 1576217593145774955007

Offset

0,2

Links

Table of n, a(n) for n=0..18.

Jean-Christophe Novelli and Jean-Yves Thibon, Free quasi-symmetric functions and descent algebras for wreath products, and noncommutative multi-symmetric functions (2008); arXiv:0806.3682 [math.CO], 2008; Discrete Math. 310 (2010), no. 24, 3584-3606. See Eq. 37.

Mathematica

terms = 19;
c[0] = 0; c[n_] := c[n] = n! - Sum[k! c[n - k], {k, 1, n - 1}];
s = (Product[1/(1 - x^k)^(2^k c[k]), {k, 1, terms}] + O[x]^terms - 1)/x;
g[x_] = ((-1/(1 + x s) + O[x]^terms) + 1);
CoefficientList[1/(1 - g[x]) + O[x]^terms, x] (* Jean-François Alcover, Feb 13 2019 *)

Crossrefs

Cf. A141309.

Sequence in context: A123549 A009704 A141308 * A012712 A012363 A012717

Adjacent sequences: A185158 A185159 A185160 * A185162 A185163 A185164

Keyword

nonn

Author

N. J. A. Sloane, Jan 23 2012

Status

approved