A396344 Expansion of x * (3+4*x-7*x^2-6*x^3-x^4-4*x^5+3*x^6+2*x^7)/((1-x) * (1+x) * (1-3*x^2-x^4+x^6)).

3, 4, 5, 10, 13, 28, 39, 86, 123, 272, 393, 870, 1261, 2792, 4051, 8970, 13019, 28828, 41845, 92658, 134501, 297828, 432327, 957310, 1389635, 3077096, 4466729, 9890766, 14357493, 31792080, 46149571, 102189906, 148339475, 328471028, 476810501, 1055810906, 1532621405, 3393713836

Offset

1,1

Links

Table of n, a(n) for n=1..38.

Index entries for linear recurrences with constant coefficients, signature (0,4,0,-2,0,-2,0,1).

Formula

a(n) = 4*a(n-2) - 2*a(n-4) - 2*a(n-6) + a(n-8).

Prog

(PARI) my(N=40, x='x+O('x^N)); Vec(x*(3+4*x-7*x^2-6*x^3-x^4-4*x^5+3*x^6+2*x^7)/((1-x)*(1+x)*(1-3*x^2-x^4+x^6)))

Crossrefs

Cf. A396345, A396346.

Sequence in context: A359486 A135114 A240789 * A191647 A195131 A361666

Adjacent sequences: A396341 A396342 A396343 * A396345 A396346 A396347

Keyword

nonn,easy

Author

Seiichi Manyama, May 23 2026

Status

approved