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 A240950 #28 Nov 19 2023 21:16:08 %S A240950 13,29,41,53,58,61,73,74,85,89,97,106,109,113,125,130,137,149,157,173, %T A240950 181,185,193,202,218,229,233,241,250,265,269,274,277,281,293,298,313, %U A240950 314,317,337,338,346,349,353,365,370,373,389,394,397,409,421,425,433 %N A240950 Numbers k such that the continued fraction for sqrt(k) has odd period, omitting those values of k of the form m^2+1. %C A240950 p^2 - n*q^2 = -1 is solvable for integers p and q. %C A240950 A031396 is the union of this sequence with A002522. %H A240950 Colin Barker, <a href="/A240950/b240950.txt">Table of n, a(n) for n = 1..1000</a> %e A240950 sqrt(13) = [3;1,1,1,1,6]. %e A240950 sqrt(29) = [5;2,1,1,2,10]. %Y A240950 Cf. A002522, A003814, A031396. %K A240950 nonn %O A240950 1,1 %A A240950 _Takao Ito_, Aug 04 2014 %E A240950 More terms from _Colin Barker_, Dec 18 2014