#include <iostream>
using namespace std;

int in[50];
int ans[4][4001];

int main(){
    int input = 0;
    while(cin >> in[input]){
        if(in[input] == EOF) break;
        input++;
    }

    for(int k = 0; k < 4; k++) ans[k][0] = 1;
    for(int n = 0; n < 4000; n++) ans[0][n] = 1;

    for(int k = 1; k < 4; k++){
        for(int n = 1; n < 4000; n++){
            ans[k][n] = ans[k - 1][n] + ans[k][n - 1];
        }
    }

    //cout << "test" << ans[3][1] << endl;

    for(int h = 0; h < input; h++){
        cout << ans[3][in[h] - 1] << endl;
    }
    return 0;
}
