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Primes of the form n*2^n + 3.
1

%I #7 Apr 26 2012 12:16:23

%S 3,5,11,67,163,10243,22531,7516192771,43980465111043,

%T 142788163609707759784588649053552643,

%U 2637188343637273091841153207596203638787

%N Primes of the form n*2^n + 3.

%C These are similar to the Woodall primes, A050918, which are primes of the form n*2^n - 1.

%e 3 = 0*2^0 + 3; 5 = 1*2^1 + 3; 11 = 2*2^2 + 3; 67 = 4*2^4 + 3

%p #choose N large, then S is the desired set

%p f:=n->n*2^n + 3:

%p S:={}:

%p for n from 0 to N do if(isprime(f(n))) then S:=S union {f(n)}: fi: od

%Y Cf. A050918, A182352, A182353.

%K nonn

%O 1,1

%A _Patrick Devlin_, Apr 25 2012