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 A261247 #5 Sep 08 2015 04:31:58 %S A261247 2,3,4,5,39,6,156,7,8,59,9,1464,10,477,11,2175,12,41571,88,13,2999,14, %T A261247 127539,244,15,108,2489,16,373,340551,17,2068,4109,18,7987764,11427, %U A261247 19,137913,406200,137,334,2709,20,12311,21,10496,15732537,40215912,1729,22,7204587,157,64719 %N A261247 Positive fundamental solution x(n) of the generalized Pell equation X^2 - D(n) Y(n) = 2 with D(n) = A261246(n). %C A261247 For the corresponding positive fundamental solution y(n) see A261248(n). %C A261247 [x(n), y(n)] gives the positive proper fundamental solution for D(n) = A261246(n), for n >= 1. %C A261247 See the comments on A261246 for this generalized Pell equation. %e A261247 See A261246. %Y A261247 Cf. A261246, A261248. %K A261247 nonn %O A261247 1,1 %A A261247 _Wolfdieter Lang_, Sep 06 2015