Brian J. Beesley wrote:
*snip*The _only_ incidence of 2^p-1 & 2^p+1 both being prime is p=2 yielding the prime pair (3, 5).
Here's a proof by induction:
Another proof: 2^n+1 is prime easily implies n is a power of 2. The only power of 2 which is prime is 2.
Regards, Josh Zelinsky [EMAIL PROTECTED]
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