A139453 - OEIS

A139453

Numbers n such that primorial(n)/2 + 512 is prime.

4, 5, 6, 7, 9, 12, 73, 129, 142, 144, 253, 455, 531, 734, 1009, 1193, 1553, 2449, 3309, 13534, 17513, 17832, 22852

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OFFSET

1,1

COMMENTS

a(24) > 25000. - Robert Price, May 22 2017

LINKS

MATHEMATICA

k = 1/2; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k + 512], Print[n]; AppendTo[a, n]], {n, 325}]; a

CROSSREFS

KEYWORD

nonn

AUTHOR

EXTENSIONS

a(12)-a(18) from Ray Chandler, Jun 16 2013

a(19)-a(23) from Robert Price, May 22 2017

STATUS

approved