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 A155173 #11 Mar 28 2014 02:08:53
%S A155173 3,5,15,21,41,59,89,101,131,141,153,155,203,209,215,231,309,351,395,
%T A155173 405,453,455,495,551,743,761,825,915,981,1001,1149,1193,1295,1343,
%U A155173 1365,1421,1529,1659,1853,2105,2171,2205,2255,2373,2409,2411,2451,2513,2561,2649
%N A155173 Short leg A of primitive Pythagorean triangles such that perimeter s is average of twin prime pairs, q=p+1, A=q^2-p^2, C=q^2+p^2, B=2*p*q, s=A+B+C; s -/+ 1 are primes.
%C A155173 With p=1, then q=2,a=3,b=4,c=5, and s=12-+1 (11, 13) both primes.
%t A155173 lst={};Do[p=n;q=p+1;a=q^2-p^2;c=q^2+p^2;b=2*p*q;s=a+b+c;If[PrimeQ[s-1]&&PrimeQ[s+1],AppendTo[lst,a]],{n,8!}];lst
%Y A155173 Cf. A020882, A020886, A020884, A020883, A024364, A024406, A155171.
%K A155173 nonn
%O A155173 1,1
%A A155173 _Vladimir Joseph Stephan Orlovsky_, Jan 21 2009
%E A155173 Name edited by _Zak Seidov_, Mar 21 2014