%I #24 Sep 08 2022 08:44:38
%S 20,160000,1280000000,10240000000000,81920000000000000,
%T 655360000000000000000,5242880000000000000000000,
%U 41943040000000000000000000000,335544320000000000000000000000000,2684354560000000000000000000000000000
%N 20^(3n+1).
%H Vincenzo Librandi, <a href="/A013766/b013766.txt">Table of n, a(n) for n = 0..200</a>
%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (8000).
%t 20^(3Range[0,10]+1) (* _Harvey P. Dale_, Jun 23 2011 *)
%o (Magma) [20^(3*n+1): n in [0..10]]; // _Vincenzo Librandi_, Jun 27 2011
%o (Maxima) makelist(20^(3*n+1),n,0,20); /* _Martin Ettl_, Oct 21 2012 */
%o (PARI) a(n)=20^(3*n+1) \\ _Charles R Greathouse IV_, Jul 10 2016
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_