A368439 Expansion of e.g.f. exp(x) / (4 - 3*exp(2*x)).

1, 7, 97, 2023, 56257, 1955527, 81570337, 3969606823, 220777431937, 13813838801287, 960354511044577, 73441487204670823, 6126887497334519617, 553733062241471461447, 53894653951229272883617, 5620230710788836168938023, 625160202763025501303191297

Offset

0,2

Links

Table of n, a(n) for n=0..16.

Formula

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

Prog

(PARI) a_vector(n) = my(v=vector(n+1)); for(i=0, n, v[i+1]=1+3*sum(j=1, i, 2^j*binomial(i, j)*v[i-j+1])); v;

Crossrefs

Cf. A080253, A337026, A368438.

Sequence in context: A058805 A305137 A132061 * A361093 A367134 A013521

Adjacent sequences: A368436 A368437 A368438 * A368440 A368441 A368442

Keyword

nonn

Author

Seiichi Manyama, Dec 24 2023

Status

approved