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 A107487 #7 Sep 07 2022 11:44:25 %S A107487 6,12,15,18,20,24,28,30,30,35,36,40,42,42,45,45,48,54,56,60,60,60,63, %T A107487 66,66,70,72,72,75,77,78,80,84,84,84,88,90,90,90,91,96,99,100,102,104, %U A107487 105,105,108,110,112,114,117,120,120,120,120,126,126 %N A107487 Ordered semiperimeters of Pythagorean triangles. %C A107487 For ordered semiperimeters of primitive Pythagorean triangles, see A020886. %H A107487 Wikipedia, <a href="https://en.wikipedia.org/wiki/Integer_triangle">Integer Triangle</a> %F A107487 a(n) = A009096(n)/2. %Y A107487 Cf. A005279, A009096, A020886. %K A107487 nonn %O A107487 1,1 %A A107487 _Lekraj Beedassy_, May 28 2005