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 A334920 #8 Feb 16 2025 08:34:00 %S A334920 4,6,8,12,4,20,8,34,20,10,40,58,24,6,74,30,26,48,8,20,26,46,112,116, %T A334920 44,226,104,80,180,52,148,38,56,28,176,50,250,20,134,178,278,60,166, %U A334920 172,84,506,50,40,34,68,60,296,50,194,130,106,372,494,148,228,252,158,552,224 %N A334920 Sum of the even side lengths of all primitive Heronian triangles with perimeter A096468(n). %H A334920 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/HeronianTriangle.html">Heronian Triangle</a> %H A334920 Wikipedia, <a href="https://en.wikipedia.org/wiki/Heronian_triangle">Heronian triangle</a> %H A334920 Wikipedia, <a href="https://en.wikipedia.org/wiki/Integer_triangle">Integer Triangle</a> %e A334920 a(1) = 4; there is one primitive Heronian triangle with perimeter A096468(1) = 12, which is [3,4,5] and its even side length is 4. %e A334920 a(6) = 20; there are two primitive Heronian triangles with perimeter A096468(6) = 36, [9,10,17] and [10,13,13]. The sum of the even side lengths is 10 + 10 = 20. %Y A334920 Cf. A096468, A334927. %K A334920 nonn %O A334920 1,1 %A A334920 _Wesley Ivan Hurt_, May 16 2020