#include<bits/stdc++.h>
using namespace std;
#define int long long
#define mod 1000000007
#define N 4100
int n,dp1[N][N],pre1[N][N],dp2[N][N],pre2[N][N];
signed main(){
    cin>>n;
    for(int i=1;i<=n;i++){
    	dp1[0][i]=(i==1);
    	dp2[0][i]=(i!=1);
    }
    for(int i=1;i<=2*n;i++){
    	pre1[0][i]=pre1[0][i-1]+dp1[0][i];
    	pre2[0][i]=pre2[0][i-1]+dp2[0][i];
    }
    for(int i=1;i<=n-1;i++){
    	for(int j=1;j<=n;j++){
    		dp1[i][j]+=pre1[i-1][j+max(1LL,i-1)-1];
    		dp2[i][j]+=pre2[i-1][j+max(1LL,i-1)-1];
    		dp1[i][j]%=mod;
    		dp2[i][j]%=mod;
    	}
    	for(int j=1;j<=2*n;j++){
    		pre1[i][j]=pre1[i][j-1]+dp1[i][j];
    		pre2[i][j]=pre2[i][j-1]+dp2[i][j];
    		pre1[i][j]%=mod;
    		pre2[i][j]%=mod;
    	}
    }
    cout<<(pre1[n-1][n-1]+pre2[n-1][n])%mod<<endl;
	return 0;
}