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A256300
Least prime p such that p+6^k is prime for all k=0,...,n.
1
2, 5, 5, 7, 7, 131, 1087, 1087, 1087, 3599111
OFFSET
0,1
COMMENTS
The function f(k;p) = p+6^k could be termed an example of a non-polynomial prime generating function.
Since 6^n (mod 11) cycles through 6,3,7,9,10,5,8,4,2,1,... there is no a(10). - John Cerkan, Jul 01 2017
LINKS
C. Rivera, Puzzle 782. Prime-Generating non-polynomials, primepuzzles.net, April 4, 2015.
PROG
(PARI) a(n)=forprime(p=1, , for(i=1, n, ispseudoprime(p+6^i)||next(2)); return(p))
CROSSREFS
Sequence in context: A121359 A082087 A263317 * A342852 A023850 A175649
KEYWORD
nonn,fini,full
AUTHOR
M. F. Hasler, Apr 05 2015
EXTENSIONS
Keywords fini,full added by John Cerkan, Jul 01 2017
STATUS
approved