using System;
using System.IO;
using System.Linq;
using System.Collections;
using System.Collections.Generic;
using System.Numerics;
using System.Diagnostics;
using System.Text;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using static System.Math;
using MethodImplOptions = System.Runtime.CompilerServices.MethodImplOptions;
using MethodImplAttribute = System.Runtime.CompilerServices.MethodImplAttribute;
using System.Runtime.CompilerServices;


static class P
{
    static void Main()
    {
        int n = int.Parse(Console.ReadLine());
        var a = Console.ReadLine().Split().Select(int.Parse).ToList();
        long res = a.First();
        long mul = 1;
        for (int i = 1; i < n; i++)
        {
            mul = mul * (n - i) / i;
            mul %= 1000000007;
            res += mul * a[i];
            res %= 1000000007;
            //Console.WriteLine(mul);
        }
        Console.WriteLine(res);
    }
}