1,1

C. Pomerance, Science News reference.

For x = 2 abs(7^2-2^11) = 1999 which is prime. So 2 is the first entry.

(PARI) g(n) = for(x=1, n, y=abs(7^x-2^11); if(ispseudoprime(y), print1(x", ")))

Sequence in context: A163116 A003306 A136585 this_sequence A014224 A077312 A140779

Adjacent sequences: A122718 A122719 A122720 this_sequence A122722 A122723 A122724

easy,nonn

Cino Hilliard (hillcino368(AT)gmail.com), Sep 23 2006