%I #21 Sep 08 2022 08:44:38

%S 16,4096,1048576,268435456,68719476736,17592186044416,

%T 4503599627370496,1152921504606846976,295147905179352825856,

%U 75557863725914323419136,19342813113834066795298816,4951760157141521099596496896

%N a(n) = 16^(2*n + 1).

%H Vincenzo Librandi, <a href="/A013721/b013721.txt">Table of n, a(n) for n = 0..100</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 (256).

%F From _Philippe Deléham_, Nov 27 2008: (Start)

%F a(n) = 256*a(n-1); a(0)=16.

%F G.f.: 16/(1-256*x).

%F a(n) = 4*A013780(n). (End)

%t NestList[256#&,16,20] (* _Harvey P. Dale_, Oct 28 2015 *)

%o (Magma) [16^(2*n+1): n in [0..15]]; // _Vincenzo Librandi_, Jun 04 2011

%o (PARI) a(n)=16^(2*n+1) \\ _Charles R Greathouse IV_, Jul 11 2016

%K nonn,easy

%O 0,1

%A _N. J. A. Sloane_