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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 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All terms are prime. a(9) > 10^5. LINKS 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 CROSSREFS Cf. A057180, A128072, A128343, A181141, A187819, A217095, A185239, A213216. Sequence in context: A084963 A139188 A064119 * A228030 A082706 A201181 Adjacent sequences:  A224981 A224982 A224983 * A224985 A224986 A224987 KEYWORD hard,nonn,more AUTHOR Robert Price, Apr 22 2013 EXTENSIONS Removed incorrect first term of "2". STATUS approved

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Last modified December 6 04:14 EST 2019. Contains 329784 sequences. (Running on oeis4.)