

A139440


Numbers n such that primorial(n)/2  4 is prime.


5



3, 4, 5, 7, 12, 15, 26, 31, 50, 71, 186, 273, 366, 1542, 1929, 3687, 4407, 15395, 15433
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OFFSET

1,1


COMMENTS

a(20) > 25000.  Robert Price, Dec 03 2016


LINKS

Table of n, a(n) for n=1..19.


MATHEMATICA

k = 1; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k  4], Print[n]; AppendTo[a, n]], {n, 2, 366}]; a


CROSSREFS

Cf. A067026, A067027, A139439A139457, A103514.
Sequence in context: A092859 A173444 A120424 * A102607 A079463 A325422
Adjacent sequences: A139437 A139438 A139439 * A139441 A139442 A139443


KEYWORD

nonn


AUTHOR

Artur Jasinski, Apr 21 2008


EXTENSIONS

a(14)a(15) from Ray Chandler, Jun 16 2013
a(16)a(17) from Robert Price, Aug 16 2016
a(18) from Robert Price, Dec 03 2016
Added missing term, 15395 by Robert Price, Dec 28 2016


STATUS

approved



