A211231 Row sums of A211230.

1, 3, 6, 10, 27, 33, 108, 108, 405, 351, 1458, 1134, 5103, 3645, 17496, 11664, 59049, 37179, 196830, 118098, 649539, 373977, 2125764, 1180980, 6908733, 3720087, 22320522, 11691702, 71744535

Offset

0,2

Links

Table of n, a(n) for n=0..28.

Formula

a(2*n) = (n+1)*3^n; a(2*n+1) = (n+9)*3^(n-1).

O.g.f.: (1+3*x-8*x^3)/(1-3*x^2)^2 = 1 + 3*x + 6*x^2 + 10*x^3 + ....

Crossrefs

Cf. A211227, A211230.

Sequence in context: A173957 A048006 A364170 * A302094 A068818 A068866

Adjacent sequences: A211228 A211229 A211230 * A211232 A211233 A211234

Keyword

nonn,easy

Author

Peter Bala, Apr 05 2012

Status

approved