OFFSET
1,1
COMMENTS
a(21) > 10^5. - Robert Price, Jan 23 2014
MATHEMATICA
Select[Range[1, 5000], PrimeQ[7^# - 8] &]
PROG
(PARI) for(n=1, 5*10^3, if(isprime(7^n-8), print1(n, ", ")))
CROSSREFS
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Oct 01 2012
EXTENSIONS
a(14)-a(20) from Robert Price, Jan 23 2014
STATUS
approved