#include<bits/stdc++.h>
using namespace std;
int N,A[110];
int main(){
    cin>>N;
    A[0]=1;
    for(int i=0;i<N;i++)A[i+3]+=A[i],A[i+5]+=A[i],A[i+7]+=A[i];
    cout<<A[N]<<endl;
}