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%I #14 Nov 08 2023 12:43:09
%S 29,31,43,59,283,1051,8219,16411,65563,1099511627803,2199023255579,
%T 17592186044443,77371252455336267181195291,
%U 1298074214633706907132624082305051
%N Primes of the form 2^k + 27.
%F a(n) = 2^A157007(n) + 27. - _Elmo R. Oliveira_, Nov 08 2023
%t a = Delete[Union[Flatten[Table[If [PrimeQ[2^n + 27] == True, 2^n + 27, 0], {n, 1, 400}]]], 1]
%o (Magma) [ a: n in [0..750] | IsPrime(a) where a is 2^n+27]; // _Vincenzo Librandi_, Nov 13 2010
%Y Cf. A000040, A157007.
%K nonn
%O 1,1
%A _Roger L. Bagula_, Mar 02 2005