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 A367195 #14 Dec 15 2023 12:36:56
%S A367195 3,5,7,11,19,29,41,61,137,181,293,11171
%N A367195 Primes p such that (2^(p-1)*(p+1) - 1) / p is prime.
%C A367195 2^(p-1)*(p+1) - 1 is the p-th term of the Cunningham chain p = n_1, n_2, ..., where n_{i+1} = 2*n_i+1 for i >= 1.
%K A367195 nonn,more
%O A367195 1,1
%A A367195 _M. Farrokhi D. G._, Nov 09 2023
%E A367195 a(12) from _Michael S. Branicky_, Nov 09 2023