#include <cstdio>
#include <cstring>
#include <iostream>
#include <string>
#include <cmath>
#include <bitset>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <algorithm>
#include <complex>
#include <unordered_map>
#include <unordered_set>
#include <random>
#include <cassert>
#include <fstream>
#define popcount __builtin_popcount
using namespace std;
typedef long long int ll;
typedef pair<int, int> P;
const ll MOD=1e9+7;
int main()
{
    int n;
    cin>>n;
    ll dp[2010];
    ll s[2010];
    for(int i=0; i<=n; i++) s[i]=i;
    for(int i=n-1; i>=2; i--){
        for(int j=1; j<=n; j++){
            dp[j]=(s[n]-s[max(0, j-i+1)]+MOD)%MOD;
        }
        for(int j=1; j<=n; j++) s[j]=(s[j-1]+dp[j])%MOD;
    }
    ll ans=0;
    for(int i=2; i<=n; i++){
        (ans+=(s[n]-s[i-1]+MOD))%=MOD;
    }
    for(int i=0; i<n; i++) s[i]=i;
    s[n]=n-1;
    for(int i=n-1; i>=2; i--){
        for(int j=1; j<=n; j++){
            dp[j]=(s[n]-s[max(0, j-i+1)]+MOD)%MOD;
        }
        for(int j=1; j<=n; j++) s[j]=(s[j-1]+dp[j])%MOD;
    }
    (ans+=s[n])%=MOD;
    cout<<ans<<endl;
    return 0;
}