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A181979 Numbers n such that (29^n - 1)/28 is prime. 1
5, 151, 3719, 49211, 77237 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
H. Dubner, Generalized repunit primes, Math. Comp., 61 (1993), 927-930.
MATHEMATICA
Select[Prime[Range[100000]], PrimeQ[(29^#-1)/28]&]
PROG
(PARI) isok(n) = isprime((29^n-1)/28); \\ Michel Marcus, Mar 13 2016
CROSSREFS
Sequence in context: A096065 A041431 A107691 * A258486 A082623 A332115
KEYWORD
hard,more,nonn
AUTHOR
Robert Price, Apr 04 2012
STATUS
approved

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Last modified April 24 04:02 EDT 2024. Contains 371918 sequences. (Running on oeis4.)