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Numbers n such that 2^n + 41*2^floor((n+1)/2) - 1 is prime.
1

%I #10 Jun 13 2017 10:28:55

%S 1,4,5,8,9,12,16,17,33,61,92,113,137,216,237,833,872,948,1308,1728,

%T 2509,4096,5457,6229,6432,6473,6868,7032,8128,8557,10449,11022,15629,

%U 29217,40756,60684

%N Numbers n such that 2^n + 41*2^floor((n+1)/2) - 1 is prime.

%C All certified primes

%o (PARI) is(n)=ispseudoprime(2^n + 41<<((n+1)\2) - 1) \\ _Charles R Greathouse IV_, Jun 13 2017

%Y Cf. A206553.

%K nonn

%O 1,2

%A _Pierre CAMI_, Feb 09 2012