//  Data Structures with Java by John R. Hubbard
//  Copyright McGraw-Hill, 2001
//  Problem 2.32 on page 51
//  Finding Mersenne primes

import schaums.dswj.Primes;

public class Pr0232
{ public static void main(String[] args) 
  { final int N=10000;
    Primes.setSize(N);
    for (int p = Primes.next(); p<30; p = Primes.next())
    { int n = (int)Math.round(Math.pow(2,p)) - 1;
      System.out.print(p + "\t2^" + p + "-1 = " + n);
      if (Primes.isPrime(n)) System.out.println(" is prime ");
      else System.out.println(" is not prime ");
    }
  }
}