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A370660 Numbers k such that (7^k + 7*k)/7 is prime. 2
1, 4, 36, 160, 342, 1086, 2094, 11524 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
If it exists, a(11) > 50000.
LINKS
PROG
(PARI) is(n) = ispseudoprime(7^(n-1)+n)
CROSSREFS
Sequence in context: A186434 A270989 A272557 * A276295 A272146 A372218
KEYWORD
nonn,hard,more
AUTHOR
Hugo Pfoertner, Feb 24 2024
STATUS
approved

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Last modified July 12 05:51 EDT 2024. Contains 374237 sequences. (Running on oeis4.)