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%I #27 Nov 17 2023 07:35:07
%S 4,6,10,18,42,78,94,114,190,322,546,3894,10318,11650,12474,20994,
%T 61810,103882,296010,636930,653638,926766
%N Numbers k such that 2^k - 11 is prime.
%C All terms are even since for odd k, 2^k - 11 is divisible by 3.
%H Henri Lifchitz and Renaud Lifchitz, <a href="http://www.primenumbers.net/prptop/searchform.php?form=2%5En-11">Search for 2^n-11</a>, PRP Top Records.
%e k = 6: 64 - 11 = 53 is prime.
%t Select[Range[4,20000],PrimeQ[2^#-11]&] (* _Vladimir Joseph Stephan Orlovsky_, Feb 26 2011*)
%Y Cf. A096502.
%Y Cf. Sequences of numbers k such that 2^k - d is prime: A000043 (d=1), A050414 (d=3), A059608 (d=5), A059609 (d=7), A059610 (d=9), this sequence (d=11), A096818 (d=13), A059612 (d=15), A059611 (d=17), A096819 (d=19), A096820 (d=21), A057220 (d=23), A356826 (d=29).
%K nonn,more
%O 1,1
%A _Labos Elemer_, Jul 13 2004
%E a(13)-a(16) from _Max Alekseyev_, a(17)-a(18) from _Henri Lifchitz_, added by _Max Alekseyev_, Feb 09 2012
%E a(19) from Lelio R Paula, added by _Max Alekseyev_, Oct 24 2013
%E a(20)-a(22) from Stefano Morozzi, added by _Elmo R. Oliveira_, Nov 16 2023