

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
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OFFSET

1,2


COMMENTS

a(29) > 25000.  Robert Price, Dec 08 2016


LINKS

Table of n, a(n) for n=1..28.


MATHEMATICA

k = 1/2; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k + 16], Print[n]; AppendTo[a, n]], {n, 752}]; a


CROSSREFS

Cf. A067026, A067027, A139439A139457, A103514.
Sequence in context: A050028 A239135 A179791 * A239263 A216293 A088497
Adjacent sequences: A139440 A139441 A139442 * A139444 A139445 A139446


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



