A013757 a(n) = 15^(3*n + 2).

225, 759375, 2562890625, 8649755859375, 29192926025390625, 98526125335693359375, 332525673007965087890625, 1122274146401882171630859375, 3787675244106352329254150390625, 12783403948858939111232757568359375

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+2): n in [0..15]]; // Vincenzo Librandi, Jun 27 2011

Mathematica

15^(3Range[0,20]+2) (* or *) NestList[3375#&,225,20] (* Harvey P. Dale, Oct 25 2011 *)

Maxima

makelist(15^(3*n+2),n,0,20); /* Martin Ettl, Oct 21 2012 */

PARI

a(n)=15^(3*n+2) \\ Charles R Greathouse IV, Jul 10 2016

Formula

From Philippe Deléham, Dec 03 2008: (Start)

a(n) = 3375*a(n-1); a(0)=225.

G.f.: 225/(1-3375*x). (End)