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A236371
Numbers n such that 7^n - 12 is prime.
9
2, 3, 4, 12, 27, 28, 34, 36, 147, 179, 242, 276, 278, 466, 735, 2371, 4548, 5606, 10324, 82899
OFFSET
1,1
COMMENTS
a(21) > 10^5.
MATHEMATICA
Select[Range[1, 100000], PrimeQ[7^# - 12] &]
PROG
(PARI) for(n=1, 5*10^5, if(isprime(7^n-12), print1(n, ", ")))
KEYWORD
nonn
AUTHOR
Robert Price, Jan 23 2014
STATUS
approved