%I
%S 3,17,593,32993,2097593,8589935681
%N Primes in the sequence n^2 + 2^n (A001580).
%C p and p^2 + 2^p are both prime only for p=3. All positive n satisfy the congruence n=3 (mod 6).  _Lekraj Beedassy_, Sep 07 2004
%C For values of n, see A064539.  _Lekraj Beedassy_, Jan 01 2007
%D J.M. De Koninck & A. Mercier, 1001 Problemes en Theorie Classique Des Nombres,Problem 165 pp. 30; 160, Ellipses Paris 2004.
%e a(3) = 593 = 2^9 +9^2. a(4) = 32993= 2^15 + 15^2.
%o (PARI) for(n=1,10^7, if(isprime(n^2+2^n),print(n^2+2^n)))
%Y Cf. A001580, A075896.
%K nonn
%O 1,1
%A _Amarnath Murthy_, Apr 21 2001
%E More terms from Jason Earls (zevi_35711(AT)yahoo.com), Aug 09 2001. Next term too large to include.
