A179422 E.g.f.: A(x) = G(G(x)) = x*G'(x) where G(x) is the g.f. of A179420.

1, 4, 36, 528, 11000, 301680, 10379376, 433371008, 21434318496, 1232928216000, 81297809313600, 6074187611551488, 509351655073262976, 47554889211476564736, 4909859201019880800000, 557309205260654645145600

Offset

1,2

Links

Paul D. Hanna, Table of n, a(n) for n = 1..150

Formula

a(n) = n*A179420(n) = n^2*A179421(n-1).

E.g.f. satisfies: x*A'(x)/A(x) = G(A(x))/G(x) where G(x) is the g.f. of A179420.

Example

E.g.f.: A(x) = x + 4*x^2/2! + 36*x^3/3! + 528*x^4/4! + 11000*x^5/5! +...
Let G(x) be the g.f. of A179420, then
. G(x) = x + 2*x^2/2! + 12*x^3/3! + 132*x^4/4! + 2200*x^5/5! +...
. G(G(x)) = x + 4*x^2/2! + 36*x^3/3! + 528*x^4/4! + 11000*x^5/5! + ...

Prog

(PARI) {a(n)=local(A=x+x^2+sum(m=3, n-1, a(m)*x^m/(m*m!))+x*O(x^n)); if(n<3, n!*polcoeff(A, n), n*n!*polcoeff(subst(A, x, A), n)/(n-2))}

Crossrefs

Cf. A179420, A179421.

Sequence in context: A024253 A052746 A145084 * A098629 A308333 A349650

Adjacent sequences: A179419 A179420 A179421 * A179423 A179424 A179425

Keyword

nonn

Author

Paul D. Hanna, Jul 28 2010

Status

approved