On 25 Oct 2001, at 10:31, Ken Kriesel wrote: > M33219278 is the smallest Mersenne Number with at least 10^7 digits, > but M33219281 is the smallest Mersenne Prime with at least 10^7 > digits.
Um, I seem to remember testing that number & confirming Rick Pali's discovery that it is _not_ prime. Perhaps it would be fair to say that M33219281 _was_ the smallest _candidate_ 10 million (decimal) digit Mersenne prime (pending LL testing). It isn't even that now. 33219281 was, is and always will be the smallest _prime_ value of n such that 2^n-1 has at least 10 million (decimal) digits; we know that a Mersenne prime _must_ have a prime exponent, therefore there cannot possibly be a 10 million (decimal) digit Mersenne prime less than M33219281. There are (AFAIK) two status changes left for M33219281: one day (maybe reasonably soon) someone will find a proper factor of this number, and one day (probably decades, centuries or even millenia away) it will be completely factored. Regards Brian Beesley _________________________________________________________________________ Unsubscribe & list info -- http://www.scruz.net/~luke/signup.htm Mersenne Prime FAQ -- http://www.tasam.com/~lrwiman/FAQ-mers
