n = int(input())
a = list(map(int,input().split()))
b1 = [1]*n
b2 = [2**(x-1) for x in a ]
b3 = [3**(x-1) for x in a ]
b4 = [4**(x-1) for x in a ]
b5 = [5**(x-1) for x in a ]
b6 = [6**(x-1) for x in a ]
b7 = [7**(x-1) for x in a ]
b8 = [8**(x-1) for x in a ]

ans = 0
for i in a:
    if i == 1:
        ans += i * sum(b1)
    elif i == 2:
        ans += i * sum(b2)
    elif i == 3:
        ans += i * sum(b3)
    elif i == 4:
        ans += i * sum(b4)
    elif i == 5:
        ans += i * sum(b5)
    elif i == 6:
        ans += i * sum(b6)
    elif i == 7:
        ans += i * sum(b7)
    elif i == 8:
        ans += i * sum(b8)
print(ans)