using System;

public class Program

{

    public static void Main()

    {

Console.Write("n = ");

        int n = int.Parse(Console.ReadLine());

        int num = 1;

        int sum = 1;

        Console.Write("The sum 1");

        while (num < n)

        {

            num++;

            sum += num;

            Console.Write(" + " +num);

        }

        Console.WriteLine(" = " + sum);

    }

    }

    }