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 A009127 #13 Aug 16 2017 06:56:29 %S A009127 210,840,1320,1890,2730,3360,4914,5250,5280,7560,7980,10290,10920, %T A009127 11880,13440,17010,18480,19656,21000,21120,24570,25410,29400,30240, %U A009127 30600,31920,32130,33000,34650,35490,41160,41580,43680,44226,45144,47250,47520,50490 %N A009127 Area of more than one Pythagorean triangle. %C A009127 Duplicate numbers in A009111. The number 210 appears twice; 840 appears three times; 341880 appears four times. See A055193 for the sequence - _T. D. Noe_, Oct 14 2013 %H A009127 Giovanni Resta, <a href="/A009127/b009127.txt">Table of n, a(n) for n = 1..10000</a> %Y A009127 Cf. A009111. %K A009127 nonn %O A009127 1,1 %A A009127 _David W. Wilson_