A013897 a(n) = 20^(5*n + 4).
160000, 512000000000, 1638400000000000000, 5242880000000000000000000, 16777216000000000000000000000000, 53687091200000000000000000000000000000, 171798691840000000000000000000000000000000000, 549755813888000000000000000000000000000000000000000
Offset: 0
Links
- Vincenzo Librandi, Table of n, a(n) for n = 0..50
- Tanya Khovanova, Recursive Sequences.
- Index entries for linear recurrences with constant coefficients, signature (3200000).
Programs
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Magma
[20^(5*n+4): n in [0..10]]; // Vincenzo Librandi, May 27 2011
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Mathematica
20^(5*Range[0,10]+4) (* or *) NestList[3200000#&,160000,10] (* Harvey P. Dale, Feb 15 2016 *)
Formula
a(n) = 3200000*a(n-1), a(0)=160000. - Vincenzo Librandi, May 27 2011
From Elmo R. Oliveira, Jul 11 2025: (Start)
G.f.: 160000/(1-3200000*x).
E.g.f.: 160000*exp(3200000*x).