A132477 Row sums of triangle A132476.

1, 4, 12, 24, 48, 96, 192, 384, 768, 1536, 3072, 6144, 12288, 24576, 49152, 98304, 196608, 393216, 786432, 1572864, 3145728, 6291456, 12582912, 25165824, 50331648, 100663296, 201326592, 402653184, 805306368, 1610612736, 3221225472, 6442450944, 12884901888

Offset: 0

Author

Gary W. Adamson, Aug 22 2007

Keywords

• nonn

Comments

A007283 = 3*2^n: (3, 6, 12, 24, 48, ...).

Examples

			a(3) = 24 = sum of row 3 terms of triangle A132476: (3 + 7 + 13 + 1).
		

Links

• Index entries for linear recurrences with constant coefficients, signature (2).

Crossrefs

Cf. A132476, A007283.

Programs

Mathematica

Join[{1,4},3 2^Range[2,40]] (* or *) Join[{1,4},NestList[2#&,12,40]] (* Harvey P. Dale, May 31 2017 *)

Formula

a(0) = 1, a(1) = 4, a(n) = 3*2^n for n>1.

G.f.: -(1+2*x+4*x^2)/(-1+2*x). - R. J. Mathar, Nov 14 2007

a(n) = 2*a(n-1) for n>1. - Harvey P. Dale, May 31 2017