OFFSET
1,1
COMMENTS
a(20) > 10^5.
EXAMPLE
9 is a member since 6^9 - 5^10 = 10077696 - 9765625 = 312071 which is a prime number.
MATHEMATICA
Select[Range[0, 100000], PrimeQ[6^# - 5^(# + 1)] &]
PROG
(PARI) is(n)=ispseudoprime(6^n-5^(n+1)) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robert Price, May 06 2016
STATUS
approved