login
A122721
Numbers n such that abs(7^n - 2^11) is prime.
0
2, 4, 5, 6, 9, 21, 41, 52, 58, 118, 130, 585, 614, 744, 881, 941, 966, 1280, 1658, 4985
OFFSET
1,1
EXAMPLE
For x = 2 abs(7^2-2^11) = 1999 which is prime. So 2 is the first entry.
PROG
(PARI) g(n) = for(x=1, n, y=abs(7^x-2^11); if(ispseudoprime(y), print1(x", ")))
CROSSREFS
Sequence in context: A003306 A250305 A136585 * A014224 A175342 A077312
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Sep 23 2006
STATUS
approved