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A256301
Least prime p such that p + k! is prime for all k = 2..n.
1
2, 3, 5, 5, 17, 107, 107, 107, 107, 82954517, 82954517, 79017245897, 79017245897, 1490524895687, 13101487760627087
OFFSET
1,1
COMMENTS
The function f(k;p) = p+(k+1)! could be called an example of a non-polynomial prime generating function.
LINKS
Carlos Rivera, Puzzle 782. Prime-Generating non-polynomials, The Prime Puzzles & Problems Connection, April 4, 2015.
PROG
(PARI) a(n)=forprime(p=1, , for(i=2, n, ispseudoprime(p+i!)||next(2)); return(p))
CROSSREFS
Sequence in context: A368706 A368674 A095296 * A226609 A370730 A157260
KEYWORD
nonn,more
AUTHOR
M. F. Hasler, Apr 05 2015
EXTENSIONS
a(12)-a(14) from John Cerkan, Jul 28 2017
Erroneous a(12) deleted and new a(14) from Khalid Sabry, Jan 25 2020
a(15) from Giovanni Resta, Jan 28 2020
STATUS
approved