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A118223 Numbers n such that n! * p(n)# - 1 is prime. 1
2, 3, 4, 9, 11, 12, 13, 50, 73, 81, 82, 115, 308, 405, 3818, 4608 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Fourteen terms found and primes proved by PrimeForm ([N+1, Brillhart-Lehmer-Selfridge]).
LINKS
EXAMPLE
3 is a term as 3! * p(3)# - 1 = 3*2*1 * 5*3*2 - 1 = 179, a prime.
CROSSREFS
Cf. A118222.
Sequence in context: A068334 A283874 A263092 * A359219 A212989 A211546
KEYWORD
nonn,more
AUTHOR
Rick L. Shepherd, Apr 16 2006
EXTENSIONS
a(15)-a(16) from Michael S. Branicky, Dec 14 2023
STATUS
approved

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Last modified March 29 06:44 EDT 2024. Contains 371265 sequences. (Running on oeis4.)