A135019 a(n) = -a(n-1) + 2a(n-2) - a(n-3), with a(0) = 0, a(1) = 1, a(2) = -3.

0, 1, -3, 5, -12, 25, -54, 116, -249, 535, -1149, 2468, -5301, 11386, -24456, 52529, -112827, 242341, -520524, 1118033, -2401422, 5158012, -11078889, 23796335, -51112125, 109783684, -235804269, 506483762, -1087875984, 2336647777

Offset

0,3

Comments

Sequence is identical to its signed second differences less first 3 terms.-

R. J. Mathar, May 17 2009

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

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

Formula

From R. J. Mathar, May 17 2009: (Start)

a(n)*(-1)^(n+1) = A002478(n-1) + 2*A002478(n-2).

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

Crossrefs

Sequence in context: A151524 A030270 A129757 * A141685 A017921 A280000

Adjacent sequences: A135016 A135017 A135018 * A135020 A135021 A135022

Keyword

sign

Author

Paul Curtz, Feb 10 2008

Extensions

More terms from R. J. Mathar, May 17 2009

Status

approved