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 A272781 Numbers n such that 6^n-5^(n+1) is prime. 0
 9, 14, 32, 48, 78, 85, 108, 134, 834, 1701, 2275, 3103, 5795, 10307, 17243, 24045, 31085, 32613, 40014 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(20) > 10^5. LINKS 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 Cf. A093713, A082103, A093717, A093793, A096185, A093794, A093795, A096186, A271883, A271884. Sequence in context: A104812 A329751 A093021 * A229543 A175201 A066793 Adjacent sequences:  A272778 A272779 A272780 * A272782 A272783 A272784 KEYWORD nonn,more AUTHOR Robert Price, May 06 2016 STATUS approved

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Last modified September 28 17:43 EDT 2020. Contains 337393 sequences. (Running on oeis4.)