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A294722 Numbers k such that (44^k - 1)/43 is prime. 1
5, 31, 167, 100511 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The number corresponding to a(4) is a probable prime.
These are the indices of base-44 repunit primes, i.e., numbers k such that A002275(k) interpreted as a base-44 number and converted to decimal is prime. - Felix Fröhlich, Nov 08 2017
LINKS
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
Sequence in context: A092496 A045904 A034353 * A237622 A239334 A180635
KEYWORD
nonn,more
AUTHOR
Paul Bourdelais, Nov 07 2017
STATUS
approved

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Last modified June 15 13:08 EDT 2024. Contains 373407 sequences. (Running on oeis4.)