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A059077 Numbers k such that 2*7^k - 3 is prime. 0
1, 3, 4, 7, 132, 253, 9040, 21888 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(9) > 27376. - Jinyuan Wang, Dec 21 2019
LINKS
MATHEMATICA
Do[ If[ PrimeQ[ 2*7^n - 3 ], Print[n] ], {n, 1, 6000} ]
PROG
(PARI) is(n)=ispseudoprime(2*7^n-3) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. A059041 (3*7^k+2 is prime).
Sequence in context: A042543 A041987 A100978 * A042707 A229348 A215758
KEYWORD
nonn,more
AUTHOR
Robert G. Wilson v, Feb 12 2001
EXTENSIONS
a(7)-a(8) from Jinyuan Wang, Dec 21 2019
STATUS
approved

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Last modified May 27 23:16 EDT 2024. Contains 372900 sequences. (Running on oeis4.)