A368013 Expansion of e.g.f. 1/(1 - exp(x) + exp(2*x)).

1, -1, -1, 5, 11, -91, -301, 3485, 15371, -228811, -1261501, 22951565, 151846331, -3264973531, -25201039501, 625232757245, 5515342166891, -155079142742251, -1538993024478301, 48364005482108525, 533289474412481051, -18523127502677822971

Offset

0,4

Links

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

Formula

a(0) = 1; a(n) = Sum_{k=1..n} (1 - 2^k) * binomial(n,k) * 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, (1-2^j)*binomial(i, j)*v[i-j+1])); v;

Crossrefs

Cf. A004700, A368016.

Sequence in context: A057727 A228503 A128454 * A188514 A301923 A353890

Adjacent sequences: A368010 A368011 A368012 * A368014 A368015 A368016

Keyword

sign

Author

Seiichi Manyama, Dec 08 2023

Status

approved