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A224984
Numbers n such that (14^n + 13^n)/27 is prime.
3
7, 13, 311, 1637, 4363, 10433, 41669, 45631
OFFSET
1,1
COMMENTS
All terms are prime.
a(9) > 10^5.
MATHEMATICA
Select[ Prime[ Range[1, 100000] ], PrimeQ[ (14^# + 13^#)/27 ]& ]
PROG
(PARI) forprime(p=3, 10^6, if(ispseudoprime((14^p + 13^p)/27), print1(p, ", ") ) ); \\ Joerg Arndt, Jul 29 2013
KEYWORD
hard,nonn,more
AUTHOR
Robert Price, Apr 22 2013
EXTENSIONS
Removed incorrect first term of "2".
STATUS
approved