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A057437
Numbers k such that 10*7^k + 1 is prime.
1
0, 1, 2, 5, 7, 9, 11, 14, 22, 45, 54, 67, 74, 321, 706, 902, 962, 11393, 13605, 17005, 17364, 27129, 27674, 29447
OFFSET
1,3
COMMENTS
a(22) > 20169. - Jinyuan Wang, Jan 21 2020
a(25) > 50000. - Michael S. Branicky, Oct 28 2024
MATHEMATICA
Do[ If[ PrimeQ[ 10*7^n + 1], Print[n]], {n, 1, 1000}]
PROG
(PARI) is(n)=ispseudoprime(10*7^n+1) \\ Charles R Greathouse IV, Jun 12 2017
CROSSREFS
Sequence in context: A169865 A286991 A029905 * A339922 A359071 A196255
KEYWORD
nonn,more,changed
AUTHOR
Robert G. Wilson v, Sep 08 2000
EXTENSIONS
First term 0 inserted by and a(18)-a(21) from Jinyuan Wang, Jan 21 2020
a(22)-a(23) from Michael S. Branicky, Mar 20 2024
a(24) from Michael S. Branicky, Oct 28 2024
STATUS
approved