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 A154664 Numbers n such that n!^2-+7493 are primes. 1
 3, 4, 5, 6, 12 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Next term is larger than 72 Next term is larger than 1000. - Harvey P. Dale, Feb 03 2016 LINKS MATHEMATICA lst={}; a=7493; Do[If[PrimeQ[n!^2-a]&&PrimeQ[n!^2+a], AppendTo[lst, n]], {n, 3*4!}]; lst Select[Range[20], AllTrue[(#!)^2+{7493, -7493}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Feb 03 2016 *) CROSSREFS Cf. A144046, A154660, A154661, A154662, A154663 Sequence in context: A048989 A299299 A103402 * A191750 A034448 A069184 Adjacent sequences:  A154661 A154662 A154663 * A154665 A154666 A154667 KEYWORD nonn AUTHOR Vladimir Joseph Stephan Orlovsky, Jan 13 2009 STATUS approved

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Last modified December 11 20:17 EST 2018. Contains 318051 sequences. (Running on oeis4.)