#include<iostream>
using namespace std;
long m=1e9+7,s;
long p(long a,long b){return b?p(a*a%m,b/2)*(b%2?a:1)%m:1;}
main()
{
	int n;cin>>n;
	long x=1;
	for(int i=0;i<n;i++)
	{
		long a;cin>>a;
		s=(s+a*x%m)%m;
		x=x*(n-i-1)%m*p(i+1,m-2)%m;
	}
	cout<<s<<endl;
}