using System;

public class Program

{

    public static void Main()

    {

        //int n;

        Console.WriteLine("Въведете броя на събираемите:");

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

        int broi,suma=0;

        Console.Write("1+3+5+...+{0}=",2*n-1);

         for(broi=1;broi<=n;broi=broi+1)

         {

            suma=suma+2*broi-1;

         }

        Console.WriteLine(suma);

    }

}