import sys sys.setrecursionlimit(10**7) n = int(input()) a = [int(i) for i in input().split()] mod = 10**9+7 def cmb(n, r, mod): if ( r<0 or r>n ): return 0 r = min(r, n-r) return g1[n] * g2[r] * g2[n-r] % mod g1 = [1, 1] # 元テーブル g2 = [1, 1] #逆元テーブル inverse = [0, 1] #逆元テーブル計算用テーブル for i in range( 2, n + 1 ): g1.append( ( g1[-1] * i ) % mod ) inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod ) g2.append( (g2[-1] * inverse[-1]) % mod ) ans = 0 for i in range(n): ans += cmb(n-1,i,mod)*a[i] ans %= mod print(ans)