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 A262772 Numbers n such that n!! - 32 is prime. 5
 7, 45, 67, 145, 411, 825, 1021, 4039, 9069, 9789, 12463, 15137, 26313, 27499 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Corresponding primes are 73, 25373791335626257947657609343, ... . a(15) > 50000. LINKS Joe McLean, Interesting Sources of Probable Primes MATHEMATICA Select[Range[0, 50000], If[#!! - 32 > 0, PrimeQ[#!! - 32]] &] PROG (MAGMA) DoubleFactorial:=func< n | &*[n..2 by -2] >; [ n: n in [7..450] | IsPrime(DoubleFactorial(n) -32) ]; // Vincenzo Librandi, Oct 01 2015 (PARI) for(n=1, 1e4, if (isprime(prod(k=0, (n-1)\2, n - 2*k ) - 32), print1(n", "))) \\ Altug Alkan, Oct 01 2015 CROSSREFS Cf. A006882, A007749, A094144, A123910, A258616. Sequence in context: A327680 A156374 A171493 * A153492 A107125 A212105 Adjacent sequences:  A262769 A262770 A262771 * A262773 A262774 A262775 KEYWORD hard,more,nonn AUTHOR Robert Price, Sep 30 2015 STATUS approved

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Last modified June 21 18:22 EDT 2021. Contains 345365 sequences. (Running on oeis4.)