n=int(input())
a=list(map(int,input().split()))
a.sort()
cnt=[0]*(2*10**5+100)
wa=[0]*(n+3)
for i in range(n-1,-1,-1):
    cnt[a[i]]+=1
    wa[i]=wa[i+1]+a[i]
for i in range(2*10**5,-1,-1):
    cnt[i]+=cnt[i+1]
ans=0
for i in range(n):
    res=0
    res+=a[i]*(n-1-i)
    res-=wa[i+1]
    for p in range(a[i],2*10**5+1,a[i]):
        if p==a[i]:res+=a[i]*(cnt[p]-1)
        else:res+=a[i]*cnt[p]

    ans+=res
print(ans)