A151746 G.f.: (1-2*x-5*x^2+4*x^3)/((1-4*x)*(1-x)^2).

1, 4, 10, 32, 118, 460, 1826, 7288, 29134, 116516, 466042, 1864144, 7456550, 29826172, 119304658, 477218600, 1908874366, 7635497428, 30541989674, 122167958656, 488671834582, 1954687338284, 7818749353090, 31274997412312, 125099989649198, 500399958596740

Offset

0,2

Links

Table of n, a(n) for n=0..25.

Formula

a(n) = 14/9+2*n/3+4^(n+1)/9, n>0. [From R. J. Mathar, Jun 17 2009]

Mathematica

CoefficientList[Series[(1-2x-5x^2+4x^3)/((1-4x)(1-x)^2), {x, 0, 30}], x] (* Harvey P. Dale, Jan 13 2015 *)

Crossrefs

Subsequence of A151735 at powers of 2.

Sequence in context: A137954 A028283 A196991 * A110145 A185631 A174520

Adjacent sequences: A151743 A151744 A151745 * A151747 A151748 A151749

Keyword

nonn

Author

N. J. A. Sloane, Jun 16 2009

Status

approved