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A245237
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Numbers n such that (48^n - 1)/47 is prime.
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3
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OFFSET
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1,1
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COMMENTS
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a(7) > 10^5.
All terms are prime.
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LINKS
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Table of n, a(n) for n=1..7.
Harvey Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930.
Henri Lifchitz, Mersenne and Fermat primes field
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MAPLE
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A245237:=n->`if`(isprime((48^n - 1)/47), n, NULL); seq(A245237(n), n=1..100000); # Wesley Ivan Hurt, Apr 12 2014
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MATHEMATICA
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Select[Prime[Range[100000]], PrimeQ[(48^# - 1)/47] &]
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PROG
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(PARI) is(n)=ispseudoprime((48^n-1)/47) \\ Charles R Greathouse IV, Jun 06 2017
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CROSSREFS
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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
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KEYWORD
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hard,more,nonn
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AUTHOR
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Robert Price, Jul 14 2014
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EXTENSIONS
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a(7) corresponds to a probable prime discovered by Paul Bourdelais, Aug 04 2020
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STATUS
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approved
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