

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
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OFFSET

1,1


COMMENTS

The function f(k;p) = p+(k+1)! could be called an example of a nonpolynomial prime generating function.


LINKS

Table of n, a(n) for n=1..15.
Carlos Rivera, Puzzle 782. PrimeGenerating nonpolynomials, 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: A146305 A079022 A095296 * A226609 A157260 A291486
Adjacent sequences: A256298 A256299 A256300 * A256302 A256303 A256304


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



