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%I #23 Jul 14 2023 08:45:02
%S 1,3,4,10,11,16,47,57,69,166,327,460,1108,4740,20760,21143,27779,
%T 34293,34311
%N Numbers k such that (2^k - k)*2^k + 1 is prime.
%C The generalization of this sequence is possible with the primes of the form (b^n +- k)*b^n +- 1.
%H Henri Lifchitz, <a href="http://www.primenumbers.net/Henri/us/NouvP1us.htm">New forms of primes</a>
%e 4 is in the sequence because (2^4 - 4)*2^4 + 1 = 193 is prime.
%t lst={}; Do[If[PrimeQ[(2^n - n)*2^n+1], AppendTo[lst,n]], {n,10^3}]; lst
%o (PARI) is(n)=ispseudoprime((2^n-n)<<n+1) \\ _Charles R Greathouse IV_, Feb 17 2017
%Y Cf. A200817, A200818, A200819, A200821, A200822, A200823, A200832.
%K nonn,more
%O 1,2
%A _Michel Lagneau_, Nov 23 2011
%E a(17)-a(19) from _Michael S. Branicky_, Jul 14 2023