import bisect
U = 2 * 10 ** 5 + 10


N = int(input())
A = list(map(int, input().split()))
A.sort()

ans = 0
for i in range(N):
    tot = 0
    L = i + 1
    for d in range(1, U):
        if A[i] * d > U:
            break
        R = bisect.bisect_left(A, A[i] * (d + 1))
        tot += (R - L) * d
        L = R
    ans += tot * A[i]

acc = 0
for i, a in enumerate(A):
    ans -= a * i - acc
    acc += a

print(ans)