package test;

import java.math.BigInteger;
import java.util.Scanner;

public class test {

    static BigInteger bg;
    static int count,level;

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        System.out.println("write count");

        try{
            count = sc.nextInt();
        }catch(Exception e){ System.out.println(e); }

        level = 1;
        bg = BigInteger.valueOf(0);

        deep();
        System.out.println("Result = "+bg);
    }

        static void deep(){
            System.out.println("level - "+level+" count - " + bg);
            bg = bg.add(BigInteger.valueOf(level));
            if(level < count){
                level++;
                deep();
            }
        }
}