At 12:59 AM 10/17/98 -0400, Foghorn Leghorn wrote:
 >
 >Second, I see that there are now some composite exponents in the ECM 
 >factoring page. Why are none of them even? Is there a technical reason 
 >that makes them less interesting?

Yes. 2^n-1 is 1 mod 2, therefore 2 is never a factor of 2^n-1. If 2^n-1 is
composite, none of its composite factors can have 2 as a factor either.

Another way to get there: Even * Any_Integer = Even, and Odd * Odd = Odd
(note that this covers all cases). Since 2^n-1 is odd, all of its factors
must be odd, and all of its factors' factors, ...

However, personally, I think George's ([EMAIL PROTECTED]) answer was more
interesting!!

-Shaun

mailto:[EMAIL PROTECTED] 
Quantum Mechanics: The dreams stuff is made of

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