//Apery.java
//probability that 3 integers have no factors in common (i.e. they are relatively prime) is 1/Apery
// Apery's constant 1.2020569031...  sum of i^-3  (1+1/2^3+1/3^3+1/4^3...)
// sum of the inverses of the cubes of the positive integers is irrational.
//reciprocal is .83190737...

//incomplete...

import java.awt.*;
import javax.swing.*;


public class Apery  {   

    public static  final int MAXBINS=30;
    
    public static void main (String[] args) {
        int maxInt, trials, a, b, c;
	int triplesThatHaveCommonFactors = 0;
        String input;

        input = JOptionPane.showInputDialog("Max range of integers","1000000000");
        maxInt = Integer.parseInt(input);
        
        input = JOptionPane.showInputDialog("Number of trials","1000000");
        trials = Integer.parseInt(input);

 /*System.out.println(""+euclid(156,330));
 System.out.println(""+euclid(330,156));
System.out.println(""+euclid(56,153));
System.out.println(""+euclid(63,72));
*/
 
        
        for (int i=0; i<trials; i++) {  
            a = (int)(Math.random()*maxInt) + 1;
            b = (int)(Math.random()*maxInt) + 1;
            c = (int)(Math.random()*maxInt) + 1;
            //System.out.println(" "+a+" "+b+" "+c);
            if (euclid(a,b) > 1)      //a and b not relatively prime
            	if (euclid(a,c) > 1)    //a and c not relatively prime
            	    if (euclid(b,c) > 1)   //b and c not relatively prime
            	    	triplesThatHaveCommonFactors++;
        }
        System.out.println(""+(1-(double)triplesThatHaveCommonFactors/trials));
    }
    
    public static int euclid(int a, int b) {
    	int r;
    	
    	if (b > a) { int x=b; b=a; a=x;	}   //swap so a>b
    	
    	while (b > 0){
    	    r = a % b;
    	    a = b;
    	    b = r;
    	}
    	return a;
    }	    
}