View Single Post
Old 2006-03-18, 09:16   #6
Mystwalker
 
Mystwalker's Avatar
 
Jul 2004
Potsdam, Germany

11001111112 Posts
Default

For a number that large, you can only try to find a factor and thus prove it's not prime.

Proving primalty of number of no special form can't be done for such big numbers. The biggest such number I heard of has been proven prime had ~15,000 digits...
Mystwalker is offline   Reply With Quote