%I #6 Dec 05 2013 19:56:31

%S 3,3,3,3,11,0,53,3,11,3,23,0,71,3,3,0,5,0,521,0,1847,0,41,3,71,3,59,0,

%T 191,0,71,0,827,0,761,3,1721,0,23,0,197,0,1229,0,59,0,1493,0,101,0,

%U 389,0,2381,0,3023,0,4691,0,6263,0,9719,0,3,0,2207,0,983,0,6701,0,239,0,347

%N Smallest prime p such that 2+p^n is a prime, or 0 if no such prime exists.

%e a(2)=a(3)=a(4)=3, as 3^2 + 2, 3^3 + 2, 3^4 + 2 are all prime.

%o (PARI) for(j=1,50, forprime (i=1,50000,if(isprime(i^j+2),print1(i,",");break())))

%K nonn

%O 1,1

%A _Amarnath Murthy_, Sep 17 2003

%E More terms from Mohammed Bouayoun (bouyao(AT)wanadoo.fr), Mar 14 2004

%E More terms from _David Wasserman_, Jun 08 2005