#include<bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC target("avx2")
#define ll long long
#define pii pair<int,int>
#define pll pair<ll,ll>
#define plx pair<ll,int>
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(),x.end()
#define vi vector<int>
#define vvi vector<vi>
#define pp pair<ll,int>
#define ub(x,i) upper_bound(all(x),i)-x.begin()
#define lb(x,i) lower_bound(all(x),i)-x.begin()
#define t3 tuple<int,int,int>
using namespace std;
const int mxn=1e5+5,k=3162,m=10000005;
int pr[mxn];
int vis[m]{0};
int get(int r){
return pr[r]==r?r:pr[r]=get(pr[r]);
}
int main(){
ios_base::sync_with_stdio(0);cin.tie(0);
int n;cin>>n;vector<int>p;ll ans=0;
for(int i=0;i<n;i++){
int x;cin>>x;p.pb(x);
}sort(all(p));p.erase(unique(all(p)),p.end());
vector<int>v;n=p.size();iota(pr,pr+n,0);
for(int i=0;i<n;i++)vis[p[i]]=i+1;
for(int i=1;i<n;i++){
if(p[i]-p[i-1]>k)v.pb(i);
}
for(int x=0;x<=k;x++){
for(int i=0;i<n;i++){
if(p[i]<=x)continue;
for(int j=p[i];j<m-x;j+=p[i]){
if(vis[j+x]&&get(vis[j+x]-1)!=get(i)){
pr[get(vis[j+x]-1)]=get(i);ans+=x;
}
}
}
}vector<t3>x;
for(auto it : v){
for(int i=0;i<it;i++){
x.pb({p[it]%p[i],i,it});
}
}sort(all(x));
for(auto [w,u,v] : x){
if(get(u)==get(v))continue;
pr[get(u)]=get(v);
ans+=w;
}cout<<ans;
}
