"Jens Kruse Andersen" <jens.k.a@...> wrote:

> The sequence of smallest prime factors is the Euclid-Mullin sequence.

It is notable that only one known factorization is incomplete:

> See for example http://oeis.org/A000945 and

> http://en.wikipedia.org/wiki/Euclid%E2%80%93Mullin_sequence

http://www.rieselprime.de/Others/EuclidMullin.htm

and in that case it suffices to show that the composite

co-factor has no prime divisor less than 127.

David