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%I #11 Jan 01 2017 17:38:08
%S 2,3,4,5,9,11,12,18,24,29,38,76,146,152,187,200,404,442,504,950,2796,
%T 5133,5683,11334,13775,20539,21253
%N Numbers n such that primorial(n)/2 + 8 is prime.
%C a(28) > 25000. - _Robert Price_, Jan 01 2017
%t k = 1/2; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k + 8], Print[n]; AppendTo[a, n]], {n, 404}]; a
%t (* Second program *)
%t Select[Range[10^3], PrimeQ[(Times @@ Prime@ Range@ #)/2 + 8] &] (* _Michael De Vlieger_, Jan 01 2017 *)
%Y Cf. A067026, A067027, A139439-A139457, A103514.
%K nonn
%O 1,1
%A _Artur Jasinski_, Apr 21 2008
%E a(18)-a(21) from _Ray Chandler_, Jun 16 2013
%E a(22)-a(27) from _Robert Price_, Jan 01 2017
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