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 A138200 #15 Sep 08 2022 08:45:33
%S A138200 1,163,31651,6200923,1215356851,238209726283,46689104402851,
%T A138200 9151064445421243,1793608631144725651,351547291702945685803,
%U A138200 68903269173764569541251,13505040758057740566199963
%N A138200 a(n) = (14^(2*n+1) + 3^(2*n+1)) / 17.
%H A138200 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (205, -1764).
%F A138200 a(n+1) = 9*a(n) + 11*14^(2*n+1), a(0) = 1.
%F A138200 O.g.f.: (14/(1-196x) + 3/(1-9x))/17. - _R. J. Mathar_, Mar 07 2008
%F A138200 a(n) = 205*a(n-1) - 1764*a(n-2), with a(0)=1, a(1)=163. - _Harvey P. Dale_, Jul 19 2013
%t A138200 Table[(14^(2n+1)+3^(2n+1))/17,{n,0,20}] (* or *) LinearRecurrence[ {205,-1764},{1,163},20] (* _Harvey P. Dale_, Jul 19 2013 *)
%o A138200 (Magma) [(14^(2*n+1)+3^(2*n+1))/17: n in [0..50]]; // _Vincenzo Librandi_, Dec 27 2010
%Y A138200 a(n) = A138199(n)/17.
%K A138200 nonn
%O A138200 0,2
%A A138200 _Reinhard Zumkeller_, Mar 05 2008