#include <bits/stdc++.h>
#define rep(i,n) for(int i=0; i<(int)(n); i++)

using namespace std;
using LL = long long;
using P = pair<int,int>;
const LL mod=1e9+7;

int main(){
	int N;
	cin >> N;
	vector<vector<LL>> ans(N);
	rep(i,N){
		LL a;
		cin >> a;
		ans[0].emplace_back(a);
	}
	rep(i,N-1){
		rep(j,ans[i].size()-1){
			ans[i+1].emplace_back((ans[i][j]+ans[i][j+1])%mod);
		}
	}
	cout << ans[N-1][0] << endl;

	return 0;
}