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%I #18 Nov 10 2015 18:53:29
%S 9,11,21,23,45,65,79,153,155,199,361,799,883,1237,1253,1753,4975,5117,
%T 5843,8179,12831
%N Numbers n such that n!! - 512 is prime.
%C Corresponding primes are 433, 9883, 13749310063, 316234142713, ... .
%C a(22) > 50000.
%H Joe McLean, <a href="http://web.archive.org/web/20091027034731/http://uk.geocities.com/nassarawa%40btinternet.com/probprim2.htm">Interesting Sources of Probable Primes</a>
%t Select[Range[0, 50000], If[#!! - 512 > 0, PrimeQ[#!! - 512]] &]
%o (PARI) for(n=1, 1e4, if (ispseudoprime(m=prod(k=0, (n-1)\2, n - 2*k) - 512), print1(n", "))) \\ _Altug Alkan_, Nov 06 2015
%Y Cf. A006882, A007749, A094144, A123910, A258616, A262772.
%K hard,more,nonn
%O 1,1
%A _Robert Price_, Nov 05 2015
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