A013756 a(n) = 15^(3*n + 1).

15, 50625, 170859375, 576650390625, 1946195068359375, 6568408355712890625, 22168378200531005859375, 74818276426792144775390625, 252511682940423488616943359375, 852226929923929274082183837890625, 2876265888493261300027370452880859375

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 (3375).

Crossrefs

Subsequence of A001024.

Programs

Magma

[15^(3*n+1): n in [0..15]]; // Vincenzo Librandi, Jun 27 2011

Mathematica

Table[15^(3n+1),{n,0,10}] (* or *) NestList[3375#&,15,10] (* Harvey P. Dale, Sep 06 2023 *)

PARI

a(n)=15^(3*n+1) \\ Charles R Greathouse IV, Jul 10 2016

Formula

From Philippe Deléham, Dec 03 2008: (Start)

a(n) = 3375*a(n-1); a(0)=15

G.f.: 15/(1-3375*x). (End)