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A072599 Numbers n such that (n!)^2 - prime(n) is prime. 1
3, 4, 5, 6, 7, 16, 109, 116, 232, 877, 934 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Values associated with 16, 109, 116 and 232 certified prime with Primo. These primes have lengths 27, 353, 382 and 900 digits, respectively.
a(10)-a(11) associated with probable primes. - Robert Price, Aug 23 2014
a(12) > 15300. - Robert Price, Aug 23 2014
LINKS
EXAMPLE
(5!)^2 - prime(5) = 120^2 - 11 = 14400 - 11 = 14389 is prime, so 5 is a term.
PROG
(PARI) for(n=1, 800, if(isprime((n!)^2-prime(n)), print1(n, ", ")))
CROSSREFS
Cf. A064769 (n such that (n!)^2 + p(n) is prime).
Sequence in context: A078305 A235324 A330373 * A095138 A026475 A101747
KEYWORD
nonn,more,hard
AUTHOR
Rick L. Shepherd, Jun 25 2002
EXTENSIONS
a(10)-a(11) from Robert Price, Aug 23 2014
STATUS
approved

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Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)