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 A051858 #9 Aug 18 2018 08:31:29 %S A051858 4,12,60,180,420,5100,60900,135720,161880,163020,218460,595140, %T A051858 1108560,2574180,2740140,3248700,3535140,3723720,3729180,8197200, %U A051858 13933920,20218440,23605320,28569240,33874680,47248920,68667480,69372420 %N A051858 Values of B (the even leg) of a Pythagorean triangle with A and C both prime and part of a twin prime. %C A051858 All terms of the sequence must be part of a Pythagorean triple of the form (2u-1), 2u*(u-1), (2u^2 - 2u + 1). - _Joshua Zucker_, May 11 2006 %Y A051858 See A051642 for the A's and A051859 for the C's. %K A051858 nonn %O A051858 1,1 %A A051858 Stuart M. Ellerstein (ellerstein(AT)aol.com), Dec 14 1999 %E A051858 a(11) corrected by the author, Jun 03 2002 %E A051858 More terms from _Joshua Zucker_, May 11 2006