A066267 Numbers k such that A066266(k) is prime.

1, 2, 5, 12, 15, 35

Offset

1,2

Comments

The next term, if it exists, is greater than 120. - Dmitry Kamenetsky, May 11 2009

The next term, if it exists, is greater than 400. - Michael S. Branicky, Aug 08 2024

Links

Table of n, a(n) for n=1..6.

Romeo Meštrović, Euclid's theorem on the infinitude of primes: a historical survey of its proofs (300 BC--2012) and another new proof, arXiv preprint arXiv:1202.3670 [math.HO], 2012-2023. - From N. J. A. Sloane, Jun 13 2012

Carlos Rivera, Puzzle 118. Primorial product numbers, The Prime Puzzles & Problems Connection.

Eric Weisstein's World of Mathematics, Primorial.

Mathematica

t={}; Do[If[PrimeQ[Times@@Table[Times@@Prime[Range[n]], {n, k}]+1], AppendTo[t, k]], {k, 35}]; t (* Jayanta Basu, May 12 2013 *)

Crossrefs

Cf. A066266, A066268, A066269, A002110, A006939, A005234.

Sequence in context: A287553 A102718 A219954 * A084122 A042143 A042467

Adjacent sequences: A066264 A066265 A066266 * A066268 A066269 A066270

Keyword

nonn,hard,more

Author

Patrick De Geest, Dec 16 2001

Extensions

Offset changed from 0 to 1 by Harry J. Smith, Feb 08 2010

Name simplified by Jon E. Schoenfield, Oct 25 2019

Status

approved