A013813 a(n) = 20^(4*n + 3).

8000, 1280000000, 204800000000000, 32768000000000000000, 5242880000000000000000000, 838860800000000000000000000000, 134217728000000000000000000000000000, 21474836480000000000000000000000000000000, 3435973836800000000000000000000000000000000000

Offset

0,1

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 (160000).

Formula

From Elmo R. Oliveira, Jul 13 2025: (Start)

G.f.: 8000/(1-160000*x).

E.g.f.: 8000*exp(160000*x).

a(n) = 160000*a(n-1).

a(n) = A013777(n)*A013793(n) = A009964(A004767(n)). (End)

Mathematica

20^(4*Range[0, 10] + 3) (* or *)
NestList[160000*# &, 8000, 10] (* Paolo Xausa, Jul 21 2025 *)

Prog

(Magma) [20^(4*n+3): n in [0..15]]; // Vincenzo Librandi, Jul 06 2011

Crossrefs

Subsequence of A009964.

Cf. A004767, A013777, A013793.

Sequence in context: A223285 A223482 A224647 * A013896 A345582 A345839

Adjacent sequences: A013810 A013811 A013812 * A013814 A013815 A013816

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved