A037632 Base 4 digits are, in order, the first n terms of the periodic sequence with initial period 2,1,3.

2, 9, 39, 158, 633, 2535, 10142, 40569, 162279, 649118, 2596473, 10385895, 41543582, 166174329, 664697319, 2658789278, 10635157113, 42540628455, 170162513822, 680650055289, 2722600221159, 10890400884638, 43561603538553

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

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

Formula

G.f.: x*(2+x+3*x^2) / ( (x-1)*(4*x-1)*(1+x+x^2) ). - R. J. Mathar, Nov 21 2011

a(n) = 4*a(n-1) + a(n-3) - 4*a(n-4). - Vincenzo Librandi, Jun 17 2012

Mathematica

LinearRecurrence[{4, 0, 1, -4}, {2, 9, 39, 158}, 40] (* Vincenzo Librandi, Jun 17 2012 *)

Prog

(Magma) I:=[2, 9, 39, 158]; [n le 4 select I[n] else 4*Self(n-1)+Self(n-3)-4*Self(n-4): n in [1..30]]; // Vincenzo Librandi, Jun 17 2012

Crossrefs

Sequence in context: A070017 A054129 A037737 * A095939 A361358 A151009

Adjacent sequences: A037629 A037630 A037631 * A037633 A037634 A037635

Keyword

nonn,base

Author

Clark Kimberling

Status

approved