OFFSET
1,1
COMMENTS
All terms are primes.
a(11) > 10^5
MATHEMATICA
Do[ p=Prime[n]; f=(7^p+4^p)/11; If[ PrimeQ[f], Print[p]], {n, 1, 9592} ]
PROG
(PARI) is(n)=ispseudoprime((7^n+4^n)/11) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
KEYWORD
hard,more,nonn
AUTHOR
Robert Price, Oct 27 2012
STATUS
approved