#include <iostream>
#include <queue>
using namespace std;
typedef long long ll;

const ll mod=1e9+7,M=3005;
ll N,a[M],b[M],s[M],res=0;
queue<ll> q[M];

int main(){
	cin>>N;
	for(int i=0;i<N-1;i++) for(int j=0;j<N-i-1;j++) q[i].push(j==N-i-2);
	a[N-1]++;
	fill(s,s+N,1);
	for(int i=1;i<N;i++){
		fill(b,b+N,0);
		ll S=0;
		for(int j=0;;j++){
			b[j]=((j==N-1?S:q[j].front())+a[j]+a[j+1])%mod;
			if(j==N-1) break;
			ll t=q[j].front(),tmp=s[j];q[j].pop();
			q[j].push(S);
			(s[j]+=S-t+mod)%=mod;
			(S+=tmp)%=mod;
		}
		for(int j=0;j<N;j++){
			(s[j]+=b[j]-a[j]+mod)%=mod;
			a[j]=b[j];
		}
	}
	for(int i=0;i<N;i++) (res+=s[i])%=mod;
	cout<<res<<endl;
}