The book is now available! 81
(another Prime Pages' Curiosity)
Prime Curios!
Curios: Curios Search:
 
Participate:
Single Curio View:   (Seek other curios for this number)

 

81 is the smallest (and only known) square such that 81*2^81-1 is prime. [Gupta]

 

  Submitted: 2003-02-08 23:56:04;   Last Modified: 2008-01-30 11:28:00.



Prime Curios! © 1999-2009 (all rights reserved)