A354554 Expansion of e.g.f. exp( x * exp(x^4) ).

1, 1, 1, 1, 1, 121, 721, 2521, 6721, 196561, 3659041, 29993041, 159762241, 1686639241, 60298558321, 987112886761, 9315623640961, 76611297104161, 2454331471018561, 69805324167893281, 1086439146068753281, 11530308934656915481

Offset

0,6

Links

Seiichi Manyama, Table of n, a(n) for n = 0..467

Formula

a(n) = n! * Sum_{k=0..floor(n/4)} (n - 4*k)^k/(k! * (n - 4*k)!).

Prog

(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(x*(exp(x^4)))))
(PARI) a(n) = n!*sum(k=0, n\4, (n-4*k)^k/(k!*(n-4*k)!));

Crossrefs

Cf. A000248, A216688, A354553.

Sequence in context: A361703 A190877 A361636 * A367720 A293566 A293507

Adjacent sequences: A354551 A354552 A354553 * A354555 A354556 A354557

Keyword

nonn

Author

Seiichi Manyama, Aug 18 2022

Status

approved