A013835 a(n) = 5^(5*n + 2).

25, 78125, 244140625, 762939453125, 2384185791015625, 7450580596923828125, 23283064365386962890625, 72759576141834259033203125, 227373675443232059478759765625, 710542735760100185871124267578125, 2220446049250313080847263336181640625

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Links

• Vincenzo Librandi, Table of n, a(n) for n = 0..100
• Tanya Khovanova, Recursive Sequences
• Index entries for linear recurrences with constant coefficients, signature (3125).

Programs

Magma

[5^(5*n+2): n in [0..15]]; // Vincenzo Librandi, Jul 07 2011

Mathematica

5^(5*Range[0,20]+2) (* or *) NestList[3125#&,25,20] (* Harvey P. Dale, Jan 02 2019 *)

Maxima

makelist(5^(5*n+2),n,0,20); /* Martin Ettl, Oct 21 2012 */

PARI

a(n)=5^(5*n+2) \\ Charles R Greathouse IV, Jul 11 2016

Formula

From Philippe Deléham, Dec 03 2008: (Start)

a(n) = 3125*a(n-1); a(0)=25.

G.f.: 25/(1-3125*x). (End)