Sum of series (1*2)+(2*3)+(3*4)+...+((n-1)*n) in Java

/*Problem: Write a program in Java to find the sum of the series * using function name product(int,int) to return the product
 * of two numbers in order to obtain each term.
 * The series :-
 * S=(1*2)+(2*3)+(3*4)+...+((n-1)*n)
 */
import java.util.*;
class series1
{
    public static void main()
    {
        int n,i;
        System.out.print("Enter the value of n : ");
        Scanner sc=new Scanner (System.in);
        n=sc.nextInt();
        int S=0,pro=0;
        for(i=1;i<n;i++)
        {
            pro=product(i,i+1);
            S=S+pro;
        }
        System.out.println("The sum is "+S);
    }
   
    public static int product(int n1,int n2)
    {
        int mul;
        mul=n1*n2;
        return(mul);
    }
}
/*Output:
 Enter the value of n : 11
 The sum is 440
 */

//Author : Mayank Rajoria