A037660 Base 4 digits are, in order, the first n terms of the periodic sequence with initial period 3,1,0.

3, 13, 52, 211, 845, 3380, 13523, 54093, 216372, 865491, 3461965, 13847860, 55391443, 221565773, 886263092, 3545052371, 14180209485, 56720837940, 226883351763, 907533407053, 3630133628212, 14520534512851, 58082138051405

Offset

1,1

Links

Table of n, a(n) for n=1..23.

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

Formula

G.f.: x*(3+x) / ( (x-1)*(4*x-1)*(1+x+x^2) ). - R. J. Mathar, Apr 30 2015

a(n) = 4*a(n-1) + a(n-3) - 4*a(n-4). - Wesley Ivan Hurt, May 02 2023

Crossrefs

Sequence in context: A086608 A291182 A037772 * A122600 A063682 A346409

Adjacent sequences: A037657 A037658 A037659 * A037661 A037662 A037663

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved