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%I #9 Jul 02 2017 21:56:11
%S 3,4,5,7,11,14,15,22,30,32,37,53,83,123,156,212,215,314,331,417,555,
%T 930,3809,3945,15738
%N Numbers n such that primorial(n)/2 + 1024 is prime.
%C a(26) > 25000. - _Robert Price_, Jul 02 2017
%t k = 1/2; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k + 1024], Print[n]; AppendTo[a, n]], {n, 325}]; a
%o (PARI) isok(n) = isprime(1024+prod(k=2, n, prime(k))); \\ _Michel Marcus_, Jul 02 2017
%Y Cf. A067026, A067027, A139439-A139457, A103514.
%K nonn
%O 1,1
%A _Artur Jasinski_, Apr 21 2008
%E a(18)-a(22) from _Ray Chandler_, Jun 16 2013
%E a(23)-a(25) from _Robert Price_, Jul 02 2017
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