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 A283274 #18 Mar 10 2025 11:46:27 %S A283274 13123110,2203385574390,2570042985510,8943387723270,826290896699730, %T A283274 9381843970167926138271390 %N A283274 Areas of triples of primitive Pythagorean triangles having the same area. %C A283274 The generators for the currently known triples are: %C A283274 a(1): (5,138),(38,77),(55,78): Charles Shedd, 1945 %C A283274 a(2): (55,3422),(61,3306),(266,2035): _Randall L Rathbun_, 1986 %C A283274 a(3): (143,2622),(869,1610),(1817,2002): _Randall L Rathbun_, 1986 %C A283274 a(4): (198,3565),(1166,2201),(2035,2438): _Randall L Rathbun_, 1986 %C A283274 a(5): (731,10434),(1122,9077),(2465,7238): _Dan Hoey_, May 18 1990 %C A283274 a(6): (352538,2999447),(1931103,2398838),(3063347,3215070): Duncan Moore, Mar 01 2017 %C A283274 The generator (a,b) gives the Pythagorean triangle (b^2+a^2,b^2-a^2,2ab) with area ab(b^2-a^2). %D A283274 R. K. Guy, Unsolved Problems in Number Theory, D21. %H A283274 Shyam Sunder Gupta, <a href="https://doi.org/10.1007/978-981-97-2465-9_23">Number Curiosities</a>, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 23, 567-604. %e A283274 The generators of a(1) give the 3 Pythagorean triangles (19069,19019,1380), (7373,4485,5852) and (9109,3059,8580). They have the areas 19019*1380/2 = 4485*5852/2 = 3059*8580/2 = 13123110 = a(1). %Y A283274 Cf. A009111. %K A283274 nonn,hard,more %O A283274 1,1 %A A283274 _Duncan Moore_, Mar 04 2017