A139454 - OEIS

A139454

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

5, 6, 9, 10, 11, 12, 17, 18, 23, 36, 48, 62, 87, 112, 131, 400, 1606, 6136, 6519, 11700

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OFFSET

1,1

COMMENTS

a(21) > 25000. - Robert Price, Jul 02 2017

LINKS

MATHEMATICA

k = 1; a = {}; Do[k = k*Prime[n]; If[PrimeQ[k - 512]&&k>512, Print[n]; AppendTo[a, n]], {n, 2, 325}]; a (* corrected by Ray Chandler, Jun 16 2013 *)

CROSSREFS

KEYWORD

nonn

AUTHOR

EXTENSIONS

Dropped 2 and a(16)-a(17) from Ray Chandler, Jun 16 2013

a(18)-a(20) from Robert Price, Jul 02 2017

STATUS

approved