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A144046 Numbers n such that |n!-107| and |n!+107| are prime. 6
3, 4, 5, 6, 7, 8, 80 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..7.

FORMULA

5!-107=13 and 5!+107=227, so 5 is a member.

MATHEMATICA

lst={}; a=107; Do[If[PrimeQ[n!-a]&&PrimeQ[n!+a], AppendTo[lst, n]], {n, 0, 20^2}]; lst

PROG

(PARI) for(n=1, 106, if(ispseudoprime(abs(n!-107))&&ispseudoprime(n!+107), print1(n", "))) \\ Charles R Greathouse IV, Oct 05 2011

CROSSREFS

Sequence in context: A037349 A037350 A014615 * A210934 A194276 A184336

Adjacent sequences:  A144043 A144044 A144045 * A144047 A144048 A144049

KEYWORD

nonn,fini,full

AUTHOR

Vladimir Joseph Stephan Orlovsky, Sep 08 2008

STATUS

approved

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Last modified November 19 18:39 EST 2019. Contains 329323 sequences. (Running on oeis4.)