A368018 Expansion of e.g.f. exp(exp(2*x) - exp(3*x)).

1, -1, -4, -5, 57, 548, 1967, -13561, -302718, -2589819, -2709911, 300801642, 5531279773, 48708116819, -142678610012, -13947271486097, -277586590571059, -2741155101562764, 15789174378252979, 1332483468802350235, 31222229349684528898, 380895661222461566625

Offset

0,3

Links

Table of n, a(n) for n=0..21.

Formula

a(0) = 1; a(n) = Sum_{k=1..n} (2^k - 3^k) * binomial(n-1,k-1) * a(n-k).

Prog

(PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=1, i, (2^j-3^j)*binomial(i-1, j-1)*v[i-j+1])); v;

Crossrefs

Cf. A355381.

Sequence in context: A335797 A041941 A220534 * A341575 A013331 A226145

Adjacent sequences: A368015 A368016 A368017 * A368019 A368020 A368021

Keyword

sign

Author

Seiichi Manyama, Dec 08 2023

Status

approved