A135078 E.g.f. A(x) = 1 + Sum_{n>=1} (1/n!)*Product_{k=0..n-1} [exp(3^k*x) - 1].

1, 1, 4, 46, 1519, 145795, 41134753, 34354750885, 85260288495316, 630102185300832652, 13884412839047621240875, 912975607895806507921828357, 179255108346123463104458490745825

Offset

0,3

Links

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

Example

A(x) = 1 + x + 4x^2/2! + 46x^3/3! + 1519x^4/4! + 145795x^5/5! +...;
A(x) = 1 + [exp(x)-1] + [exp(x)-1][exp(3x)-1]/2! + [exp(x)-1][exp(3x)-1][exp(9x)-1]/3! + [exp(x)-1][exp(3x)-1][exp(9x)-1][exp(27x)-1]/4! +...

Prog

(PARI) {a(n)=n!*polcoeff(1+sum(j=1, n, (1/j!)*prod(k=0, j-1, 1*exp(3^k*x)-1)), n)}

Crossrefs

Cf. variants: A135077, A135079.

Sequence in context: A324228 A002077 A113096 * A195243 A269005 A107766

Adjacent sequences: A135075 A135076 A135077 * A135079 A135080 A135081

Keyword

nonn

Author

Paul D. Hanna, Nov 24 2007

Status

approved