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 A209120 Numbers n such that (33^n - 1)/32 is prime. 1
 3, 197, 3581, 6871, 183661 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS H. Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930. H. Lifchitz, Mersenne and Fermat primes field Index to primes in various ranges, form ((k+1)^n-1)/k MATHEMATICA Select[Prime[Range[100]], PrimeQ[(33^#-1)/32]&] PROG (PARI) isok(n) = isprime((33^n-1)/32); \\ Michel Marcus, Mar 13 2016 CROSSREFS Sequence in context: A101382 A000724 A309749 * A336250 A256407 A256406 Adjacent sequences:  A209117 A209118 A209119 * A209121 A209122 A209123 KEYWORD hard,more,nonn AUTHOR Robert Price, Mar 05 2012 EXTENSIONS a(5) corresponds to a probable prime discovered by Paul Bourdelais, Dec 31 2018 STATUS approved

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Last modified December 8 22:49 EST 2021. Contains 349596 sequences. (Running on oeis4.)