A141397 a(n) = 3*a(n-1) + A001651(n+1).

1, 5, 19, 62, 193, 587, 1771, 5324, 15985, 47969, 143923, 431786, 1295377, 3886151, 11658475, 34975448, 104926369, 314779133, 944337427, 2833012310, 8499036961, 25497110915, 76491332779, 229473998372, 688421995153, 2065265985497, 6195797956531, 18587393869634

Offset

0,2

Comments

Row sums of triangle A141396.

Links

Table of n, a(n) for n=0..27.

Index entries for linear recurrences with constant coefficients, signature (4,-2,-4,3)

Formula

G.f.: ( -1-x-x^2 ) / ( (1+x)*(3*x-1)*(x-1)^2 ). a(n) = (-1)^n/16 -3*n/4 -3/2 +13*3^(n+1)/16. - R. J. Mathar, Feb 16 2011

Example

a(2) = 19 = 3*a(1) + A001651(3) = 3*5 + 4 where A001651(3) = 4.
a(2) = 19 = sum of row 2 terms of triangle A141396: (4 + 6 + 9).

Prog

(PARI) Vec((-1-x-x^2) / ((1+x)*(3*x-1)*(x-1)^2) + O(x^40)) \\ Michel Marcus, Jan 21 2015

Crossrefs

Cf. A141396, A001651.

Sequence in context: A072111 A173627 A295288 * A305779 A143131 A036677

Adjacent sequences: A141394 A141395 A141396 * A141398 A141399 A141400

Keyword

nonn,easy

Author

Gary W. Adamson, Jun 29 2008

Status

approved