#!/bin/python3

import sys

def solve(A):
    a=[]
    m=0
    sum=0
    l=[]
    for i in range(0,len(A)):
        h=len(A)-i
        for j in range(0,h):
            a.append(A[j])
        #a.append(A[i])
    
    for i in range(0,len(a)):
        #i=i+1
        h=len(a)-i-1
        for j in range(h,0,-1):
            sum=(sum+a[i]+a[j])%1000000007
            l.append(a[i])
            l.append(a[j])
    #print(l)
    return sum-len(a)
if __name__ == "__main__":
    n = int(input().strip())
    A = list(map(int, input().strip().split(' ')))
    result = solve(A)
    print(result)