A037765 Base 4 digits are, in order, the first n terms of the periodic sequence with initial period 3,0,2,1.

3, 12, 50, 201, 807, 3228, 12914, 51657, 206631, 826524, 3306098, 13224393, 52897575, 211590300, 846361202, 3385444809, 13541779239, 54167116956, 216668467826, 866673871305, 3466695485223, 13866781940892, 55467127763570, 221868511054281, 887474044217127, 3549896176868508, 14199584707474034

Offset

1,1

Links

Table of n, a(n) for n=1..27.

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

Formula

G.f.: x*(3+2*x^2+x^3) / ( (x-1)*(4*x-1)*(1+x)*(x^2+1) ). - R. J. Mathar, May 02 2015

a(n) = 4*a(n-1) + a(n-4) - 4*a(n-5). - Wesley Ivan Hurt, Apr 25 2023

a(n) = floor(67*4^n/85). - Christian Krause, Jun 06 2026

Mathematica

Table[FromDigits[PadRight[{}, n, {3, 0, 2, 1}], 4], {n, 30}] (* Harvey P. Dale, May 09 2018 *)

Crossrefs

Sequence in context: A180879 A391835 A180283 * A037653 A229665 A092443

Adjacent sequences: A037762 A037763 A037764 * A037766 A037767 A037768

Keyword

nonn,base,easy,changed

Author

Clark Kimberling

Extensions

a(24)-a(27) from Christian Krause, Jun 06 2026

Status

approved