A013791 a(n) = 9^(4*n + 3).

729, 4782969, 31381059609, 205891132094649, 1350851717672992089, 8862938119652501095929, 58149737003040059690390169, 381520424476945831628649898809, 2503155504993241601315571986085849, 16423203268260658146231467800709255289

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..200
• Tanya Khovanova, Recursive Sequences
• Index entries for linear recurrences with constant coefficients, signature (6561).

Crossrefs

Subsequence of A001019.

Programs

Magma

[9^(4*n+3): n in [0..15]]; // Vincenzo Librandi, Jun 28 2011

Mathematica

9^(4*Range[0,20]+3) (* or *) NestList[6561#&,729,20] (* Harvey P. Dale, Jul 30 2021 *)

PARI

a(n)=9^(4*n+3) \\ Charles R Greathouse IV, Jul 11 2016

Formula

From Philippe Deléham, Dec 07 2008: (Start)

a(n) = 6561*a(n-1); a(0)=729.

G.f.: 729/(1-6561*x).

a(n) = 81*A013790(n). (End)