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%I #8 Jul 14 2015 01:29:41
%S 1,2,4,8,10,16,86,344,406,424,2324,6358,11026,11804,48926,266744
%N Numbers n such that 2^n + n - 1 is a prime.
%C The associated prime list is 2, 5, 19, 263, 1033, 65551, 77371252455336267181195349 etc.
%C a(17) > 335000. - _Giovanni Resta_, Mar 26 2014
%e For n=2, 2^2+2-1=5 is prime. For n=4, 2^4+4-1=19 is prime.
%t fQ[n_] := PrimeQ[ 2^n + n - 1]; k = 1; lst = {}; While[k < 35000, If[ fQ@k, AppendTo[ lst, k]; Print@k]; k ++ ] (* _Robert G. Wilson v_, Feb 26 2010 *)
%K nonn
%O 1,2
%A _Vincenzo Librandi_, Feb 09 2010
%E Definition corrected, leading 1 inserted, 5 terms appended - _R. J. Mathar_, Feb 13 2010
%E a(12) - a(15) from _Robert G. Wilson v_, Feb 26 2010
%E a(16) from _Giovanni Resta_, Mar 26 2014