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 A031664 #14 Aug 18 2021 00:10:32 %S A031664 119797,176521,250169,327409,420193,422789,425393,426698,530345, %T A031664 533261,643645,653305,766154,774929,780218,783754,905026,906929, %U A031664 910741,914561,918389,920306,926069,1061629,1219657,1224077,1232941,1241837 %N A031664 Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 76. %Y A031664 Subsequence of A003814. %K A031664 nonn %O A031664 1,1 %A A031664 _David W. Wilson_ %E A031664 First term 5777 removed by _Georg Fischer_, Jun 16 2019