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 A272345 Numbers n such that 8^n-7^(n-1) is prime. 1
 1, 3, 5, 29, 41, 83, 471, 725, 1277, 10271, 15069, 97731 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(13) > 10^5. LINKS EXAMPLE 5 is a member since 8^5 - 7^4 = 32768 - 2401 = 30367 which is a prime number. MATHEMATICA Select[Range[0, 100000], PrimeQ[8^# - 7^(# - 1)] &] PROG (PARI) is(n)=ispseudoprime(8^n-7^(n-1)) \\ Charles R Greathouse IV, Jun 13 2017 CROSSREFS Cf. A093713, A082103, A093717, A093793, A096185, A093794, A093795, A096186, A271883, A271884. Sequence in context: A321069 A141578 A327748 * A346659 A067200 A106089 Adjacent sequences:  A272342 A272343 A272344 * A272346 A272347 A272348 KEYWORD nonn,more AUTHOR Robert Price, Apr 26 2016 STATUS approved

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Last modified December 8 10:14 EST 2021. Contains 349594 sequences. (Running on oeis4.)