A194787 E.g.f. A(x) = G(x)^G(x) where G(x) = 1 + x*G(x)^G(x) is the e.g.f. of A194786.

1, 1, 4, 27, 272, 3630, 60714, 1221864, 28779120, 776965680, 23662145160, 802640076480, 30014281406856, 1226796674341056, 54417859649294400, 2603641529587553280, 133660822187138916480, 7328549084322230968320, 427437378614564995967424

Offset

0,3

Links

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

Formula

a(n) = A194786(n+1)/(n+1).

Example

E.g.f.: A(x) = 1 + x + 4*x^2/2! + 27*x^3/3! + 272*x^4/4! + 3630*x^5/5! +...
where A(x) = G(x)^G(x) and G(x) is the e.g.f. of A194786:
G(x) = 1 + x + 2*x^2/2! + 12*x^3/3! + 108*x^4/4! + 1360*x^5/5! +...

Prog

(PARI) {a(n)=local(A=1+x); for(i=1, n, A=1+x*(A+x*O(x^n))^A); n!*polcoeff(A^A, n)}

Crossrefs

Cf. A194786.

Sequence in context: A161633 A052871 A104653 * A020558 A259485 A362699

Adjacent sequences: A194784 A194785 A194786 * A194788 A194789 A194790

Keyword

nonn

Author

Paul D. Hanna, Sep 02 2011

Status

approved