A382675 a(n) = 4 - 15 * 2^n + 12 * 3^n.

1, 10, 52, 208, 736, 2440, 7792, 24328, 74896, 228520, 693232, 2095048, 6315856, 19009000, 57149872, 171695368, 515577616, 1547715880, 4645113712, 13939273288, 41825684176, 125492781160, 376509800752, 1129592316808, 3388902779536, 10166959996840, 30501383306992, 91505156553928

Offset

0,2

Links

Paolo Xausa, Table of n, a(n) for n = 0..2000

Index entries for linear recurrences with constant coefficients, signature (6,-11,6).

Formula

From Stefano Spezia, Mar 05 2026: (Start)

G.f.: (1 + x)*(1 + 3*x)/((1 - x)*(1 - 2*x)*(1 - 3*x)).

E.g.f.: exp(x)*(4 - 15*exp(x) + 12*exp(2*x)). (End)

Mathematica

A382675[n_] := 12*3^n - 15*2^n + 4; Array[A382675, 30, 0] (* or *)
LinearRecurrence[{6, -11, 6}, {1, 10, 52}, 30] (* Paolo Xausa, Mar 12 2026 *)

Prog

(PARI) a(n) = 4-15*2^n+12*3^n;

Crossrefs

Column k=2 of A382673.

Row n=2 of A382673.

Sequence in context: A092966 A281401 A050494 * A367460 A200035 A119543

Adjacent sequences: A382672 A382673 A382674 * A382676 A382677 A382678

Keyword

nonn,easy

Author

Seiichi Manyama, Apr 03 2025

Extensions

More terms from Paolo Xausa, Mar 12 2026

Status

approved