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A059676
Numbers n such that n*5^n - 1 is prime.
13
8, 14, 42, 384, 564, 4256, 6368, 21132, 27180, 96584, 349656, 545082
OFFSET
1,1
MATHEMATICA
Do[ If[ PrimeQ[ n*5^n - 1 ], Print[ n ]], {n, 1, 4000} ]
PROG
(PARI) is(n)=ispseudoprime(n*5^n-1) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
Sequence in context: A121866 A301961 A250478 * A242198 A111050 A009453
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Feb 05 2001
EXTENSIONS
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008
a(11)-a(12) from Harvey link by Ray Chandler, Apr 10 2016
STATUS
approved