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A309527
Numbers k such that 6^k + 17 is prime.
0
1, 2, 3, 5, 8, 10, 19, 27, 79, 198, 565, 787, 2183, 3811, 4748, 6210, 7887, 8965, 13303, 20125, 23433, 28797
OFFSET
1,2
COMMENTS
a(20) > 14000. - Daniel Starodubtsev, Apr 17 2020
EXAMPLE
3 is in the sequence because 6^3 + 17 = 233, which is prime.
PROG
(PARI) lista(nn)=for(k=0, nn, if(ispseudoprime(6^k+17), print1(k", ")))
KEYWORD
nonn,more,hard,less
AUTHOR
Daniel Starodubtsev, Aug 06 2019
EXTENSIONS
a(17)-a(18) from Daniel Starodubtsev, Mar 16 2020
a(19) from Daniel Starodubtsev, Apr 17 2020
a(20)-a(22) from Michael S. Branicky, Mar 14 2023
STATUS
approved