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 A196121 #5 Mar 30 2012 18:57:49 %S A196121 13,11,37,26,23,73,22,47,39,121,74,59,181,33,52,107,83,253,46,146,65, %T A196121 111,337,44,61,94,191,143,433,78,242,179,541,55,71,97,148,299,69,91, %U A196121 219,661,118,362,263,793,66,104,141,214,431,185,311,937,166,506 %N A196121 Positive integers c for which there is a 4-Pythagorean triple (a,b,c) satisfying a<=b. %C A196121 See A195770 for definitions of k-Pythagorean triple, primitive k-Pythagorean triple, and lists of related sequences. %t A196121 (See A196119.) %Y A196121 Cf. A195770, A196119, A196124. %K A196121 nonn %O A196121 1,1 %A A196121 _Clark Kimberling_, Sep 28 2011