On Fri, 09 Feb 2001 16:30:04 -0500, Jud McCranie wrote:

>At 06:59 PM 2/9/2001 +0000, habibnajafi@... wrote:

>>I have found tabulary that a perfect no. -1 or -3 is never a prime.

>>but I can't not find mathmatical solution to that.

>

>6 is perfect, but 6-1 is prime.

These numbers are less likely to be prime, since all perfect numbers

end in '6' or '8' in decimal, making one value or the other divisible

by 5.

Another counterexamples, of course, is 6-3.

I was unable to find any primes using pfgw, but it seems to tend to

discard smaller numbers by factoring them to themselves, which I am

not sure how to get around.

Nathan