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 A113171 #9 Jul 18 2025 04:52:49
%S A113171 660,1092,1140,1155,1260,1320,1365,1380,1428,1540,1560,1740,1785,1820,
%T A113171 1860,1980,1995,2184,2220,2340,2380,2415,2436,2460,2508,2580,2604,
%U A113171 2660,2805,2820,2856,2860,2940,3003,3036,3060,3108,3120,3135,3180,3192,3220,3300
%N A113171 Short legs 'A' of exactly 7 primitive Pythagorean triangles.
%H A113171 Ray Chandler, <a href="/A113171/b113171.txt">Table of n, a(n) for n = 1..10000</a>
%F A113171 a^2+b^2=c^2
%e A113171 Examples of triples: 660.779.1021, 660.989.1189, 660.2989.3061, 660.4331.4381, 660.12091.12109, 660.27221.27229, 660.108899.108901
%e A113171 1092.1325.1717, 1092.1595.1933, 1092.6035.6133, 1092.8245.8317, 1092.33115.33133, 1092.74525.74533, 1092.298115.298117
%t A113171 PythagoreanAs[a_]:=(q={};k=0;Do[y=(a^2+b^2)^0.5;c=IntegerPart[y];If[c==y,p=0;If[GCD[a,b,c]==1,AppendTo[q,a.b.c];k++ ]],{b,a+1,a^2}];PrependTo[q,k];q);lst={};Do[If[PythagoreanAs[n][[1]]==7,Print[n];AppendTo[lst,n]],{n,6*10^2,2*10^3}];lst
%Y A113171 Cf. A056866 Orders of non-solvable groups. A093006 Referring to the triangle in A093005, sequence contains the least term with maximal number of divisors. A138605 Short legs of more than 3 primitive Pythagorean triangles. A033993 Numbers that are divisible by exactly four different primes.
%K A113171 nonn
%O A113171 1,1
%A A113171 _Vladimir Joseph Stephan Orlovsky_, Aug 25 2008
%E A113171 More terms from _Ray Chandler_, Jan 22 2020