A037520 Base 3 digits are, in order, the first n terms of the periodic sequence with initial period 2,1,0.

2, 7, 21, 65, 196, 588, 1766, 5299, 15897, 47693, 143080, 429240, 1287722, 3863167, 11589501, 34768505, 104305516, 312916548, 938749646, 2816248939, 8448746817, 25346240453, 76038721360, 228116164080, 684348492242

Offset

1,1

Links

Table of n, a(n) for n=1..25.

Index entries for linear recurrences with constant coefficients, signature (3,0,1,-3)

Formula

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

Mathematica

With[{c=PadRight[{}, 27, {2, 1, 0}]}, Table[FromDigits[Take[c, n], 3], {n, 25}]] (* Harvey P. Dale, Nov 08 2011 *)

Crossrefs

Sequence in context: A159972 A106271 A027990 * A218836 A331722 A052911

Adjacent sequences: A037517 A037518 A037519 * A037521 A037522 A037523

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved