This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A013830 #24 Sep 08 2022 08:44:38 %S A013830 4,4096,4194304,4294967296,4398046511104,4503599627370496, %T A013830 4611686018427387904,4722366482869645213696,4835703278458516698824704, %U A013830 4951760157141521099596496896,5070602400912917605986812821504 %N A013830 a(n) = 4^(5*n + 1). %H A013830 Vincenzo Librandi, <a href="/A013830/b013830.txt">Table of n, a(n) for n = 0..100</a> %H A013830 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a> %H A013830 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1024). %F A013830 From _Philippe Deléham_, Nov 30 2008: (Start) %F A013830 a(n) = 1024*a(n-1), n > 0; a(0)=4. %F A013830 G.f.: 4/(1-1024*x). (End) %t A013830 4^(5Range[0,20]+1) (* or *) NestList[1024#&,4,20] (* _Harvey P. Dale_, Oct 04 2011 *) %o A013830 (Magma) [4^(5*n+1): n in [0..15]]; // _Vincenzo Librandi_, Jul 07 2011 %o A013830 (PARI) a(n)=4^(5*n+1) \\ _Charles R Greathouse IV_, Jul 11 2016 %Y A013830 Cf. A000302 (4^n), A016861 (5*n+1). %K A013830 nonn,easy %O A013830 0,1 %A A013830 _N. J. A. Sloane_