A362274 Expansion of e.g.f. 1/(1-x*exp(x*exp(x))).

1, 1, 4, 27, 232, 2465, 31416, 467173, 7940080, 151824177, 3225664720, 75386002901, 1921987809336, 53085088574713, 1578989028324904, 50320957240554645, 1710595789688360416, 61783832256587799137, 2362794061464082513440, 95380148553556615501717

Offset

0,3

Links

Winston de Greef, Table of n, a(n) for n = 0..398

Formula

a(n) = n! * Sum_{i=0..n} Sum_{j=0..n-i} i^j * j^(n-i-j) / (j! * (n-i-j)!).

Prog

(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1-x*exp(x*exp(x)))))

Crossrefs

Cf. A000949, A362273, A362275.

Cf. A362245.

Sequence in context: A354588 A276029 A160883 * A328978 A379192 A185655

Adjacent sequences: A362271 A362272 A362273 * A362275 A362276 A362277

Keyword

nonn

Author

Seiichi Manyama, Apr 13 2023

Status

approved