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 A051859 #14 Jun 27 2021 12:33:17
%S A051859 5,13,61,181,421,5101,60901,135721,161881,163021,218461,595141,
%T A051859 1108561,2574181,2740141,3248701,3535141,3723721,3729181,8197201,
%U A051859 13933921,20218441,23605321,28569241,33874681,47248921,68667481,69372421
%N A051859 Values of C (the hypotenuse) of a Pythagorean triangle with A (the short leg) and C both prime and part of a twin prime.
%C A051859 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 12 2006
%H A051859 Harvey P. Dale, <a href="/A051859/b051859.txt">Table of n, a(n) for n = 1..1000</a>
%F A051859 A051858 + 1, or 2*A051891^2 - 2*A051891 + 1, or 2*A051892^2 + 2*A051892 + 1. - _Joshua Zucker_, May 12 2006
%t A051859 tppQ[{a_,b_,c_}]:=AllTrue[{a,c},PrimeQ]&&AnyTrue[a+{2,-2},PrimeQ] && AnyTrue[ c+{2,-2},PrimeQ]; Select[Table[{2n-1,2n(n-1),2n^2-2n+1},{n,2,10000}],tppQ][[All,3]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 27 2021 *)
%Y A051859 See A051642 for the A's and A051858 for the B's.
%Y A051859 Subset of A067756.
%K A051859 nonn
%O A051859 1,1
%A A051859 Stuart M. Ellerstein (ellerstein(AT)aol.com), Dec 14 1999
%E A051859 More terms from _Joshua Zucker_, May 12 2006