#include <bits/stdc++.h>
using namespace std;
int main() {
  int x;
  cin >> x;
  if (x == 1) {
    cout << 1 << endl;
  } else if (x == 2) {
    cout << 2 << endl;
  } else if (x == 3) {
    cout << 6 << endl;
  } else if (x == 4) {
    cout << 20 << endl;
  } else if (x == 5) {
    cout << 70 << endl;
  } else if (x == 6) {
    cout << 252 << endl;
  } else if (x == 7) {
    cout << 924 << endl;
  } else if (x == 8) {
    cout << 3432 << endl;
  } else if (x == 9) {
    cout << 12870 << endl;
  } else if (x == 10) {
    cout << 48620 << endl;
  }
  return 0;
}
