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 A070139 #11 Feb 16 2025 08:32:46 %S A070139 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0, %T A070139 0,2,0,0,0,0,0,0,0,0,0,0,0,1,0,2,0,0,0,1,0,0,0,0,0,0,0,0,0,3,0,0,0,0, %U A070139 0,0,0,2,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,1 %N A070139 Number of isosceles integer triangles with perimeter n having integral area. %C A070139 a(n) = A051516(n) - A024153(n). %H A070139 Seiichi Manyama, <a href="/A070139/b070139.txt">Table of n, a(n) for n = 1..1000</a> %H A070139 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HeronianTriangle.html">Heronian Triangle</a>. %H A070139 R. Zumkeller, <a href="/A070080/a070080.txt">Integer-sided triangles</a> %Y A070139 Cf. A051516, A024153, A059169, A070145. %K A070139 nonn %O A070139 1,36 %A A070139 _Reinhard Zumkeller_, May 05 2002