n = int(input())
A = list(map(int, input().split()))
ma = max(A) + 1
cnt = [0] * ma
for a in A:
    cnt[a] += 1
A.sort()
for i in range(ma - 1):
    cnt[i + 1] += cnt[i]
plus = 0
minus = 0
tot = sum(A)
for i, a in enumerate(A):
    plus += a * (n - i - 1)
    minus += tot
    tot -= a
    for j in range(a, ma, a):
        if j + a < ma:
            c = cnt[j + a - 1] - cnt[j - 1]
            minus -= c * j
        else:
            c = n - cnt[j - 1]
            minus -= c * j
    
print(plus - minus)