A020530 a(n) = 8^n + 2^(n+1).

3, 12, 72, 528, 4128, 32832, 262272, 2097408, 16777728, 134218752, 1073743872, 8589938688, 68719484928, 549755830272, 4398046543872, 35184372154368, 281474976841728, 2251799813947392, 18014398510006272

Offset

0,1

Comments

4th Fibonacci polynomial evaluated at 2^n.

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..140

Index entries for linear recurrences with constant coefficients, signature (10,-16)

Formula

G.f. 3*(1-6*x)/((8*x-1)*(2*x-1)). - R. J. Mathar, Jun 07 2016

a(n) = 3*A103334(n+1). - R. J. Mathar, Jun 07 2016

E.g.f.: (2 + exp(6*x))*exp(2*x). - Ilya Gutkovskiy, Jun 07 2016

Maple

with(combinat, fibonacci):seq(fibonacci(4, 2**i), i=0..24);

Mathematica

Table[Fibonacci[4, 2^i], {i, 0, 30}] (* Vladimir Joseph Stephan Orlovsky, Nov 03 2009 *)
LinearRecurrence[{10, -16}, {3, 12}, 30] (* Harvey P. Dale, May 04 2018 *)

Prog

(Magma) [8^n + 2^(n+1): n in [0..30]]; // Vincenzo Librandi, Apr 26 2011

Crossrefs

Sequence in context: A175836 A293138 A319948 * A337061 A147998 A052676

Adjacent sequences: A020527 A020528 A020529 * A020531 A020532 A020533

Keyword

nonn,easy

Author

Simon Plouffe

Status

approved