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A121931 Numbers n such that (n!)^8 + 1 is prime. 0
0, 1, 2, 58, 75, 347 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Corresponding primes of the form (n!)^8 + 1 are {2,2,257,...}.

a(7) > 7000. - Robert Price, Aug 26 2014

LINKS

Table of n, a(n) for n=1..6.

MATHEMATICA

Do[f=(n!)^8+1; If[PrimeQ[f], Print[{n, f}]], {n, 1, 75}]

CROSSREFS

Cf. A060890, A051855, A046029, A002981.

Sequence in context: A030263 A090743 A104494 * A156507 A285148 A115610

Adjacent sequences:  A121928 A121929 A121930 * A121932 A121933 A121934

KEYWORD

more,nonn,hard

AUTHOR

Alexander Adamchuk, Sep 10 2006

EXTENSIONS

347 from Ryan Propper, Jan 03 2008

STATUS

approved

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Last modified January 25 01:49 EST 2020. Contains 331229 sequences. (Running on oeis4.)