A037561 Base 4 digits are, in order, the first n terms of the periodic sequence with initial period 2,2,1.

2, 10, 41, 166, 666, 2665, 10662, 42650, 170601, 682406, 2729626, 10918505, 43674022, 174696090, 698784361, 2795137446, 11180549786, 44722199145, 178888796582, 715555186330, 2862220745321, 11448882981286, 45795531925146

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

Crossrefs

Sequence in context: A110684 A197175 A297047 * A135512 A317328 A368678

Adjacent sequences: A037558 A037559 A037560 * A037562 A037563 A037564

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved