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 A046087 #19 Feb 16 2025 08:32:38
%S A046087 4,12,15,24,21,35,40,45,60,56,63,55,77,84,80,72,99,91,112,117,105,143,
%T A046087 144,140,132,120,165,180,153,176,168,195,156,187,171,220,221,208,209,
%U A046087 255,247,264,260,252,231,240,285,224,273,312,308,253,323,288,299,272
%N A046087 Middle member 'b' of the primitive Pythagorean triples (a,b,c) ordered by increasing c, then b.
%H A046087 Ivan Neretin, <a href="/A046087/b046087.txt">Table of n, a(n) for n = 1..10000</a>
%H A046087 F. Richman, <a href="http://math.fau.edu/Richman/mla/pythag3s.htm">Pythagorean Triples</a>
%H A046087 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PythagoreanTriple.html">Pythagorean Triple</a>
%t A046087 maxHypo = 389; r[b_, c_] := Reduce[0 < a <= b < c && a^2 + b^2 == c^2, a, Integers]; Reap[Do[r0 = r[b, c]; If[r0 =!= False, {a0, b0, c0} = {a, b, c} /. ToRules[r0]; If[GCD[a0, b0, c0] == 1, Print[b0]; Sow[b0]]], {c, 1, maxHypo}, {b, 1, maxHypo}]][[2, 1]] (* _Jean-François Alcover_, Oct 22 2012 *)
%Y A046087 Cf. A046086, A020882.
%K A046087 nonn,look
%O A046087 1,1
%A A046087 _Eric W. Weisstein_