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 A013722 #28 Sep 08 2022 08:44:38
%S A013722 17,4913,1419857,410338673,118587876497,34271896307633,
%T A013722 9904578032905937,2862423051509815793,827240261886336764177,
%U A013722 239072435685151324847153,69091933913008732880827217
%N A013722 a(n) = 17^(2*n + 1).
%C A013722 Sum_{n>=0} 1/a(n) = 17/288. - _Jaume Oliver Lafont_, Feb 04 2009
%H A013722 Vincenzo Librandi, <a href="/A013722/b013722.txt">Table of n, a(n) for n = 0..200</a>
%H A013722 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>
%H A013722 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (289).
%F A013722 From _Philippe Deléham_, Nov 28 2008: (Start)
%F A013722 a(n) = 289*a(n-1), a(0)=17.
%F A013722 G.f.: 17/(1-289*x). (End)
%p A013722 seq(17^(2*n+1),n=0..10); # _Nathaniel Johnston_, Jun 25 2011
%t A013722 17^(2*Range[0,10]+1) (* or *) NestList[289#&,17,10] (* _Harvey P. Dale_, Aug 15 2012 *)
%o A013722 (Magma) [17^(2*n+1): n in [0..15]]; // _Vincenzo Librandi_, Jun 26 2011
%o A013722 (PARI) a(n)=17^(2*n+1) \\ _Charles R Greathouse IV_, Jul 11 2016
%Y A013722 Bisection of A001026 (17^n).
%Y A013722 Cf. A013708-A013721, A013723-A013729.
%K A013722 nonn,easy
%O A013722 0,1
%A A013722 _N. J. A. Sloane_