3_1 for

package lab1;

import static java.lang.Math.*;

import java.util.Scanner;

public class Lab3_1 {

	public static void main(String[] args) {

		double a,e,s1,s2;
		int L, M;

		Scanner input = new Scanner(System.in);

		System.out.print("L");
        L = input.nextInt();

        System.out.print("M");
        M = input.nextInt();

        System.out.print("a");
        a = input.nextDouble();

        input.close();

        e = 1.0;
        s1 = 0;
        s2 = 0;
        for (int k = 1; k<=M; k++) {
        	e *= a * (pow(k,2)+1.0);
        	s2 += (pow(k,2)/(a+1.0));

        }

        for(int j=1; j<=L; j++) {

        	s1 += ((j+2.0)/j);
        }


        System.out.print(e+s1-s2);
	}

}