A013734 a(n) = 4^(3*n+1).

4, 256, 16384, 1048576, 67108864, 4294967296, 274877906944, 17592186044416, 1125899906842624, 72057594037927936, 4611686018427387904, 295147905179352825856, 18889465931478580854784, 1208925819614629174706176

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Comments

Additive digital root of a(n) = 4. - Miquel Cerda, Jul 02 2016

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..160
• Tanya Khovanova, Recursive Sequences
• Index entries for linear recurrences with constant coefficients, signature (64).

Crossrefs

Cf. A013735.

Programs

Magma

[4^(3*n+1): n in [0..20]]; // Vincenzo Librandi, May 25 2011

Maple

seq(4^(3*n+1),n=0..13); # Nathaniel Johnston, Jun 26 2011

Mathematica

4^(3*Range[0,20]+1) (* or *) NestList[64#&,4,20] (* Harvey P. Dale, Feb 22 2016 *)

PARI

Vec(4/(1-64*x) + O(x^99)) \\ Altug Alkan, Jul 05 2016

PARI

a(n)=2^(6*n+2) \\ Charles R Greathouse IV, Jul 11 2016

Formula

a(n) = 64*a(n-1), n>0 ; a(0)=4. G.f.: 4/(1-64*x). a(n)=4*A089357(n). - Philippe Deléham, Nov 24 2008

E.g.f.: 4*exp(64*x). - Ilya Gutkovskiy, Jul 02 2016