Primorial prime
From Wikipedia, the free encyclopedia.

A primorial prime is a number that is one less or one more than a primorial and also a prime number. The first eight primorials are

5, 7, 29, 31, 211, 2309, 2311, 30029

The largest known primorial primes are p₅₉₀# - 1 and p₁₃₉₁# + 1.

Reference

The article on primorials at http://mathworld.wolfram.com/Primorial.html, from Wolfram Research, the makers of Mathematica 4.

The original article can be found at: http://en.wikipedia.org/wiki/Primorial_prime.
All text is available under the terms of the GNU Free Documentation License.