On Tue, 26 Oct 1999, Alexander Kruppa wrote:
>Hello all,
>
>a simple Number Theory question. Is always
>
>(2^p-1) / p ,odd prime p, divisible by 3 ?
I assume you mean truncated integer division, as real division makes no sense
here.
It isn't if p=3 (7/3=2), but 2^p-2 is divisible by 3. (2^n) mod 3 is 1 if n is
even, 2 if n is odd.
If p=5, 2^p-1=31, and 31/5=6, so it is true for 5.
phma
_________________________________________________________________
Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm
Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
