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A100598 Numbers n such that (prime(n)-1)! + prime(n)^8 is prime. 0
1, 2, 4, 5, 8, 10 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

n={1, 2, 4, 5, 8, 10} yields primes p(n)={2, 3, 7, 11, 19, 29}. There are no more such n up to n=100. Computed in collaboration with Ray Chandler.

LINKS

J. V. Post, Math Pages.

EXAMPLE

a(1) = 1 because (prime(1)-1)! + prime(1)^8 = (2-1)! + 2^8 = 257 is the smallest prime of that form.

a(5) = 8 because (prime(8)-1)! + prime(8)^8 = (19-1)! + 19^8 = 304888344611713861001750412961 is the 5th smallest prime of that form.

MATHEMATICA

lst={}; Do[p=Prime[n]; If[PrimeQ[(p-1)!+p^8], AppendTo[lst, n]], {n, 10^2}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Sep 08 2008]

CROSSREFS

Cf. A100858.

Sequence in context: A101394 A095031 * A191535 A079537 A094591 A189093

Adjacent sequences:  A100595 A100596 A100597 * A100599 A100600 A100601

KEYWORD

nonn,less

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Nov 30 2004

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com) at the suggestion of Andrew Plewe, Jun 08 2007

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Last modified February 15 07:42 EST 2012. Contains 205717 sequences.