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A156907 G.f.: A(x) = 1 + x*exp( Sum_{k>=1} [A(2^k*x) - 1]^k/k ). 3
1, 1, 2, 18, 476, 38358, 11363548, 15060027956, 92500603618872, 2483766272252845670, 279689176516909339664044, 129570236404446129260308225372, 244562582019257683819447274838128648 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Conjectured to consist entirely of integers.

LINKS

Table of n, a(n) for n=0..12.

EXAMPLE

G.f.: A(x) = 1 + x + 2*x^2 + 18*x^3 + 476*x^4 + 38358*x^5 +...

...

A(x) = 1 + x*exp( [A(2x)-1] + [A(4x)-1]^2/2 + [A(8x)-1]^3/3 +... ).

PROG

(PARI) {a(n)=local(A=1+x+x*O(x^n)); for(i=1, n, A=1+x*exp(sum(k=1, n, (subst(A, x, 2^k*x+x*O(x^n))-1)^k/k))); polcoeff(A, n)}

CROSSREFS

Cf. A156908.

Sequence in context: A082402 A208055 A306655 * A053916 A277037 A015203

Adjacent sequences:  A156904 A156905 A156906 * A156908 A156909 A156910

KEYWORD

nonn

AUTHOR

Paul D. Hanna, Mar 04 2009

STATUS

approved

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Last modified May 25 00:03 EDT 2022. Contains 354047 sequences. (Running on oeis4.)