A360896 G.f. satisfies A(x) = 1 + x * A(x * (1 - x^2)).

1, 1, 1, 1, 0, -2, -5, -4, 9, 39, 46, -101, -516, -624, 2021, 9704, 8847, -58363, -230932, -65902, 2085381, 6301393, -5195375, -84748630, -174659303, 535875052, 3703162955, 3578704451, -39485091237, -163826467050, 88095454403, 2675998434838, 6571312338031

Offset

0,6

Links

Seiichi Manyama, Table of n, a(n) for n = 0..952

Formula

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

Prog

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

Crossrefs

Cf. A360894, A360897.

Cf. A360885.

Sequence in context: A296208 A324142 A339809 * A084432 A071297 A356875

Adjacent sequences: A360893 A360894 A360895 * A360897 A360898 A360899

Keyword

sign

Author

Seiichi Manyama, Feb 25 2023

Status

approved