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A064769
Numbers n such that (n!)^2 + prime(n) is prime.
1
1, 2, 3, 5, 9, 17, 65, 222, 1720, 2975, 3494, 10489, 17948
OFFSET
1,2
COMMENTS
Term <= 1720 certified prime with Primo.
Next term, if it exists, is greater than 2700. - Ryan Propper, Nov 05 2005
a(10)-a(13) are probable primes.
a(14) > 20000. - Robert Price, Aug 29 2014
EXAMPLE
(5!)^2 + prime(5) = 120^2 + 11 = 14400 + 11 = 14411 is prime, so 5 is a term.
PROG
(PARI) for(n=1, 300, if(isprime((n!)^2+prime(n)), print1(n, ", ")))
CROSSREFS
Cf. A046029, A072599 (n such that (n!)^2 - prime(n) is prime).
Sequence in context: A137155 A014227 A334816 * A320641 A365640 A047021
KEYWORD
nonn
AUTHOR
Jason Earls, Oct 18 2001
EXTENSIONS
1720 from Ryan Propper, Nov 05 2005
a(10)-a(13) from Robert Price, Aug 29 2014
STATUS
approved