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 A100595 Numbers n such that (prime(n)-1)! + prime(n)^9 is prime. 0
 9, 10, 17, 137 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS There are no more such n up to n=150. Computed in collaboration with Ray Chandler. LINKS FORMULA Numbers n such that (prime(n)-1)! + prime(n)^9 is prime, where prime(n) is the n-th prime. EXAMPLE a(1) = 9 because (prime(9)-1)! + prime(9)^9 = (23-1)! + 23^9 = 1124000729578760341463 is the smallest prime of this form. a(2) = 10 because (prime(10)-1)! + prime(10)^9 = (29-1)! + 29^9 = 304888344611713875008649975869 is the 2nd smallest prime of this form. a(3) = 17, but prime(17) = 59 yields a number that would take 2 full lines of this page; and a(4) = 137 because prime(137) = 773 yields a prime of this form which is 1975 digits long. Note also that 773 = prime(137) = prime(prime(34)). MATHEMATICA lst={}; Do[p=Prime[n]; If[PrimeQ[(p-1)!+p^9], AppendTo[lst, n]], {n, 12^2}]; lst [From Vladimir Joseph Stephan Orlovsky, Sep 08 2008] CROSSREFS Cf. A100858. Sequence in context: A191380 A088036 A217935 * A107433 A090570 A131417 Adjacent sequences:  A100592 A100593 A100594 * A100596 A100597 A100598 KEYWORD easy,nonn AUTHOR Jonathan Vos Post, Nov 30 2004 STATUS approved

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