Consider six consecutive positive integers. Show that there is a prime number that divides exactly one of them.

(In reply to One conjecture dead, one still alive by Steve Herman)

That's good stuff, Steve! Your counter examples clearly show that the general problem isn't quite so easy as n=6 (or n=7..14). Congratulations!

Browsing through another perplexus puzzle I stumbled upon an interesting comment from Art M, which lead me to have a closer look at Bertrand's Postulate and its extension, which seems to be very relevant for our general case. What do you think?

Posted by JLo on 2006-09-09 04:37:53