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 A294722 Numbers n such that (44^n - 1)/43 is prime. 1
 5, 31, 167, 100511 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Number corresponding to a(4) is a probable prime. These are the indices of base-44 repunit primes, i.e., numbers n such that A002275(n) interpreted as base-44 number and converted to decimal is prime. - Felix Fröhlich, Nov 08 2017 LINKS P. Bourdelais, A generalized repunit conjecture MATHEMATICA ParallelMap[ If[ PrimeQ[(44^# - 1)/43], #, Nothing] &, Prime@Range @ 10000] (* Robert G. Wilson v, Nov 25 2017 *) PROG (PFGW) ABC2 (44^\$a-1)/43 // -f{2*\$a} a: primes from 2 to 1000000 (PARI) is(n) = ispseudoprime((44^n-1)/43) \\ Felix Fröhlich, Nov 08 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. Sequence in context: A092496 A045904 A034353 * A237622 A239334 A180635 Adjacent sequences:  A294719 A294720 A294721 * A294723 A294724 A294725 KEYWORD nonn,more AUTHOR Paul Bourdelais, Nov 07 2017 STATUS approved

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Last modified December 14 17:44 EST 2019. Contains 329979 sequences. (Running on oeis4.)