A367592 Expansion of 1/((1-x) * (1-4*x)^3).

1, 13, 109, 749, 4589, 26093, 140781, 730605, 3679725, 18097645, 87303661, 414459373, 1941186029, 8987616749, 41199871469, 187228759533, 844358755821, 3782116386285, 16838816966125, 74563177424365, 328550363440621, 1441256130749933, 6296699479008749

Offset

0,2

Links

Table of n, a(n) for n=0..22.

Index entries for linear recurrences with constant coefficients, signature (13,-60,112,-64).

Formula

a(n) = ((9*n^2+21*n+14) * 4^(n+1) - 2)/54.

Prog

(PARI) a(n) = ((9*n^2+21*n+14)*4^(n+1)-2)/54;

Crossrefs

Partial sums of A038845.

Cf. A055580, A367591.

Sequence in context: A002648 A055840 A243417 * A163845 A075143 A005769

Adjacent sequences: A367589 A367590 A367591 * A367593 A367594 A367595

Keyword

nonn,easy

Author

Seiichi Manyama, Nov 24 2023

Status

approved