from bisect import bisect_left
n = int(input())
A = list(map(int,input().split()))
A.sort()
cum = [0]
for a in A:
    cum.append(cum[-1]+a)
ans = 0

for i in range(n-1)[::-1]:
    l = A[i+1]
    a = A[i]
    dl = l//a
    lind = i+1
    while lind < n:
        dl += 1
        rind = bisect_left(A,dl*a)
        ans += (rind-lind)*a
        ans -= (cum[rind]-cum[lind])-(rind-lind)*a*(dl-1)
        lind = rind
print(ans)