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 A097270 #5 Feb 16 2025 08:32:54 %S A097270 3,7,9,11,12,15,16,19,21,23,24,27,28,31,33,35,36,39,43,44,47,48,49,51, %T A097270 55,56,57,59,60,63,64,67,69,71,75,76,77,79,81,83,84,87,88,91,92,93,95, %U A097270 96,99,103,105,107,108,111,112,115,119,120,121,123,124,127,129,131,132 %N A097270 Numbers that are the difference of two nonzero squares but not the sum of two nonzero squares. %C A097270 Intersection of A024352 (difference of squares) and complement of A000404 (sum of squares). %H A097270 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SumofSquaresFunction.html">Sum of Squares Function.</a> %Y A097270 Cf. A000404, A024352, A097268-A097271. %K A097270 nonn %O A097270 1,1 %A A097270 _Ray Chandler_, Aug 19 2004