#include<iostream>
using namespace std;
int main(){
    int a[25]={1,2,3,5,7,9,13,18,21,27,34,39,46,54,61,72,83,92,106,118,130,145,162,176,193};
    int n;
    cin>>n;
    cout<<a[n];
    return 0;
}