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%I #14 Dec 15 2023 12:36:56
%S 3,5,7,11,19,29,41,61,137,181,293,11171
%N Primes p such that (2^(p-1)*(p+1) - 1) / p is prime.
%C 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 nonn,more
%O 1,1
%A _M. Farrokhi D. G._, Nov 09 2023
%E a(12) from _Michael S. Branicky_, Nov 09 2023