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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.

A334761 Perimeters of Pythagorean triangles whose hypotenuse divides the difference of squares of its long and short legs.

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%I A334761 #14 Jun 19 2022 23:23:31
%S A334761 60,120,180,240,300,360,390,420,480,540,600,660,680,720,780,840,900,
%T A334761 960,1020,1080,1140,1170,1200,1260,1320,1360,1380,1400,1440,1500,1560,
%U A334761 1620,1680,1740,1800,1860,1920,1950,1980,2030,2040,2100,2160,2220,2280,2340,2400
%N A334761 Perimeters of Pythagorean triangles whose hypotenuse divides the difference of squares of its long and short legs.
%C A334761 The smallest terms corresponding to 2,...,5 triangles are a(15) = 780, a(191) = 9360, a(3324) = 159120, and a(19433) = 928200, respectively. - _Giovanni Resta_, May 11 2020
%H A334761 Giovanni Resta, <a href="/A334761/b334761.txt">Table of n, a(n) for n = 1..10000</a>
%H A334761 Wikipedia, <a href="https://en.wikipedia.org/wiki/Integer_triangle">Integer Triangle</a>
%H A334761 Wikipedia, <a href="http://en.wikipedia.org/wiki/Pythagorean_triple">Pythagorean Triple</a>.
%H A334761 <a href="/index/Ps#PyTrip">Index entries related to Pythagorean Triples</a>.
%e A334761 a(1) = 60; the triangle [15,20,25] has perimeter 60. The difference of squares of its long and short leg lengths is (20^2 - 15^2) = 400 - 225 = 175 and 25|175.
%t A334761 Reap[Do[s = Solve[x^2 + y^2 == (p-x-y)^2 && z^2 == x^2 + y^2 && 0<x<y<z && p - x - y > 0, {x, y, z}, Integers]; If[s != {} && AnyTrue[{x, y , z} /. s, Mod[#[[2]]^2 - #[[1]]^2, #[[3]]] == 0 &], Print@Sow@p], {p, 12, 1000, 2}]][[2, 1]] (* _Giovanni Resta_, May 11 2020 *)
%Y A334761 Cf. A005044, A010814.
%K A334761 nonn
%O A334761 1,1
%A A334761 _Wesley Ivan Hurt_, May 10 2020
%E A334761 Terms a(31) and beyond from _Giovanni Resta_, May 11 2020