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 A245237 Numbers n such that (48^n - 1)/47 is prime. 3
 19, 269, 349, 383, 1303, 15031 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(7) > 10^5. All terms are prime. LINKS Harvey Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930. Henri Lifchitz, Mersenne and Fermat primes field MAPLE A245237:=n->`if`(isprime((48^n - 1)/47), n, NULL); seq(A245237(n), n=1..100000); # Wesley Ivan Hurt, Apr 12 2014 MATHEMATICA Select[Prime[Range[100000]], PrimeQ[(48^# - 1)/47] &] PROG (PARI) is(n)=ispseudoprime((48^n-1)/47) \\ Charles R Greathouse IV, Jun 06 2017 CROSSREFS Cf. A028491, A004061, A004062, A004063, A004023, A005808, A004064, A016054, A006032, A006033, A006034, A006035, A127995, A127996, A127997, A127998, A127999, A098438, A128002, A128003, A128004, A128005, A240765, A242797, A243279. Sequence in context: A016254 A016302 A253217 * A141942 A181043 A142899 Adjacent sequences:  A245234 A245235 A245236 * A245238 A245239 A245240 KEYWORD hard,more,nonn AUTHOR Robert Price, Jul 14 2014 STATUS approved

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Last modified December 7 18:12 EST 2019. Contains 329847 sequences. (Running on oeis4.)