Re: Misprint

*To*: mathgroup at smc.vnet.net*Subject*: [mg111078] Re: Misprint*From*: Bill Rowe <readnews at sbcglobal.net>*Date*: Mon, 19 Jul 2010 02:11:17 -0400 (EDT)

On 7/18/10 at 1:05 AM, lehin.p at gmail.com (Alexey) wrote: >It seems that there is a misprint on the page >http://www.wolfram.com/products/mathematica/usersanduses/mersenne. >html We read that "In June 1999 an international group of >mathematicians, computer scientists, and hobbyists <...> discovered >that 2^6972593-1 is prime." But it is not true: In[3]:= >PrimeQ[2^26972593 - 1] Out[3]= False Given <http://en.wikipedia.org/wiki/Mersenne_prime#cite_note-17> and <http://primes.utm.edu/mersenne/> both indicate 2^6972593-1 is prime and cite references, it does seem like the issue is not a typo on the web page you found. Rather, it seems there is a problem with PrimeQ. Note, I didn't wait long enough for PrimeQ to return a response on my system and consequently did not reproduce your result.