import java.util.*;
import java.lang.*;
import java.io.*;

class Main {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();

        long odd = 0l;
        long even = 0l;
        long[] as = new long[n+1];
        as[1] = 1l;
        odd = 1l;
       
        for (int i=2; i<=n; i++) {
            if (i % 2 == 0) {
                as[i] = i * odd;
                even += as[i];
            }else{
                as[i] += i * even;
                odd += as[i];
            }
        }
        
        System.out.println(as[n]);
    }
}