//Aamrun , 11th July, 2022

#include <iostream>
using namespace std;

int F(int n,int x,int y) {
  if (n == 0) {
    return x + y;
  }

  else if (y == 0) {
    return x;
  }

  return F(n - 1, F(n, x, y - 1), F(n, x, y - 1) + y);
}

int main() {
  cout << "F(1,3,3) = "<<F(1,3,3)<<endl;
  return 0;
}