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 A031605 #14 Aug 18 2021 00:10:32 %S A031605 6010,6322,6481,9337,12713,16609,17386,18181,21898,22193,22789,23393, %T A031605 26605,27917,28585,32125,34297,39733,40529,41333,41738,42554,45569, %U A031605 45994,46421,48149,49466,49909,53629,57373,59293,61357,65357,66377,70130,70657 %N A031605 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 17. %Y A031605 Subsequence of A003814. %K A031605 nonn %O A031605 1,1 %A A031605 _David W. Wilson_ %E A031605 First term 290 removed by _Georg Fischer_, Jun 16 2019