n = int(input())
A = list(map(int, input().split()))
N = max(A) + 10
cnt = [0] * (N + 1)
tot = [0] * (N + 1)

for a in A:
    cnt[a] += 1
    tot[a] += a
for i in range(N):
    cnt[i + 1] += cnt[i]
    tot[i + 1] += tot[i]

ans = 0
for i in range(1, N + 1):
    c = cnt[i] - cnt[i - 1]
    if c == 0:
        continue
    
    ans += c * tot[i - 1]
    j = i
    while j < N:
        cc = cnt[min(j + i - 1, N)] - cnt[j]
        tt = tot[min(j + i - 1, N)] - tot[j]
        ans += c * (tt - cc * j)
        j += i
    
print(ans)