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A139443
Numbers n such that primorial(n)/2 + 16 is prime.
5
1, 2, 3, 5, 6, 8, 13, 25, 26, 30, 34, 63, 75, 138, 149, 672, 752, 1067, 1256, 1370, 3357, 4120, 6672, 7201, 7469, 8738, 9426, 11608
OFFSET
1,2
COMMENTS
a(29) > 25000. - Robert Price, Dec 08 2016
MATHEMATICA
k = 1/2; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k + 16], Print[n]; AppendTo[a, n]], {n, 752}]; a
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Apr 21 2008
EXTENSIONS
a(1)=1 inserted and program corrected, a(18)-a(20) from Ray Chandler, Jun 16 2013
a(21)-a(28) from Robert Price, Dec 08 2016
STATUS
approved