#include<iostream>
#include<map>

using namespace std;

typedef map<int,int> imap;

int main() {
 int n;
 cin >> n;
 if(n<3){ cout << 1 << endl; return 0; }
 if(n==3){ cout << 3 << endl; return 0; }
 imap a, b, c;
 int ans=0,m=int(1e9)+7;
 a[1]=1;b[2]=1;c[3]=1;
 while(a.size()>0||b.size()>0||c.size()>0){
  imap x, y, z;
  for(auto it=a.begin();it!=a.end();it++){
   int k=it->first,v=it->second;
   if(k+2<n){y[k+2]=(y[k+2]+v)%m;}
   else if(k+2==n){ans=(ans+v)%m;}
   if(k+3<n){z[k+3]=(z[k+3]+v)%m;}
   else if(k+3==n){ans=(ans+v)%m;}
  }
  for(auto it=b.begin();it!=b.end();it++){
   int k=it->first,v=it->second;
   if(k+1<n){x[k+1]=(x[k+1]+v)%m;}
   else if(k+1==n){ans=(ans+v)%m;}
   if(k+3<n){z[k+3]=(z[k+3]+v)%m;}
   else if(k+3==n){ans=(ans+v)%m;}
  }
  for(auto it=c.begin();it!=c.end();it++){
   int k=it->first,v=it->second;
   if(k+1<n){x[k+1]=(x[k+1]+v)%m;}
   else if(k+1==n){ans=(ans+v)%m;}
   if(k+2<n){y[k+2]=(y[k+2]+v)%m;}
   else if(k+2==n){ans=(ans+v)%m;}
  }
  a=x;b=y;c=z;
 }
 cout << ans << endl;
 return 0;
}