#include<bits/stdc++.h>
using namespace std;

#define int long long
#define pb emplace_back
#define sz(v) (int)(v.size())
#define all(v) (v.begin(),v.end())
#define M 1000000007

signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	int n;
	cin >> n;
	vector<int> v(n);
	for(int i = 0;i<n;i++)
		cin >> v[i];

	int dp[n];
	dp[0] = 1;
	for(int i = 1;i<=n;i++){
		dp[i] = (dp[i-1] * (n - i))/i;
	}
	// dp stores the value of ncr from r = 0 to r = n

	int ans = 0;
	for(int i = 0;i<n;i++){
		ans += ((dp[i] * v[i]) % M); 
	}

	cout << ans << " ";
	return 0;
}