show/hide this revision's text 2 Much better answer!

You want:

What about tacking on 1/47059 to your last example? This extension is suggested by the definition of Sylvester's sequence. Of course we got lucky that 2*3*11*23*31 + 1 = 47059 was prime.

http://en.wikipedia.org/wiki/Sylvester's_sequence. Oh wait, I missed the word "prime"... Never mind.

show/hide this revision's text 1

You want: http://en.wikipedia.org/wiki/Sylvester's_sequence. Oh wait, I missed the word "prime"... Never mind.