A131562 a(n)= -3a(n-1) -3a(n-2)-2a(n-3), a(0)=1, a(1)=-2, a(2)=2.

1, -2, 2, -2, 4, -10, 22, -44, 86, -170, 340, -682, 1366, -2732, 5462, -10922, 21844, -43690, 87382, -174764, 349526, -699050, 1398100, -2796202, 5592406, -11184812, 22369622, -44739242, 89478484, -178956970, 357913942, -715827884, 1431655766, -2863311530

Offset

0,2

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Index entries for linear recurrences with constant coefficients, signature (-3,-3,-2).

Formula

|v(n)| = 2^n+A130772(n); 2*|v(n)|-|v(n+1)|= 2*A057079(n), where v(n)=a(n+1)-a(n) are first differences.

O.g.f.: (1+x-x^2)/((1+2x)(1+x+x^2). a(n)=(-1)^n*A130707(n). - R. J. Mathar, Jul 07 2008

Binomial transform yields A130151 without the first two terms. - R. J. Mathar, Jul 07 2008

Mathematica

LinearRecurrence[{-3, -3, -2}, {1, -2, 2}, 40] (* Harvey P. Dale, Jan 11 2017 *)

Crossrefs

Cf. A130707.

Sequence in context: A213270 A307522 A130707 * A260786 A374663 A067920

Adjacent sequences: A131559 A131560 A131561 * A131563 A131564 A131565

Keyword

sign

Author

Paul Curtz, Aug 27 2007

Extensions

Edited by R. J. Mathar, Jul 07 2008

Status

approved