#include <bits/stdc++.h>
using namespace std;
// #define double long double
#define int long long
#define pb push_back
#define vi vector<int>
#define vpii vector<pair<int,int>>
#define MAX 200005
#define f first
#define s second
const int INF = 1e18;
const int mod = 2019201997;
#define pii pair<int,int>
int sum(int a,int b){return ((a%mod)+(b%mod))%mod;}
int mul(int a,int b){return ((a%mod)*(b%mod))%mod;}
vi dsu(MAX),sz(MAX);
int find(int a){
if(dsu[a]==a) return a;
return dsu[a]=find(dsu[a]);
}
void unite(int a,int b){
a=find(a); b=find(b);
if(a==b) return;
if(sz[a]<sz[b]) swap(a,b);
sz[a]+=sz[b]; dsu[b]=a;
}
vector<array<int,3>> edges;
void solve(){
int n; cin>>n;
vi val(1e7+2);
vi v(n); for(int i=0;i<n;i++) cin>>v[i],dsu[i]=i,sz[i]=1;
sort(v.begin(),v.end()); v.erase(unique(v.begin(),v.end()),v.end());
for(int i=0;i<v.size();i++){
// cout<<v[i]<<" 23\n";
val[v[i]]=i+1;
}
vpii nxt(1e7+2,{INF,INF}); int j=n-1;
for(int i=1e7;i>0;i--){
if(v[j]==i) nxt[i]={i,j+1},j--;
else nxt[i]=nxt[i+1];
}
for(int i=1;i<=1e7;i++){
if(!val[i]) continue;
for(int j=i;j<=1e7;j+=i){
if(nxt[j+(j==i)].f>=j+i) continue;
edges.pb({ nxt[j+(j==i)].f % i , val[i] , nxt[j+(j==i)].s } );
}
}
sort(edges.begin(),edges.end());
int ans=0;
for(auto u : edges){
if(find(u[1])==find(u[2])) continue;
ans+=u[0]; unite(u[1],u[2]);
}
cout<<ans<<endl;
}
int32_t main(){
// freopen("walk.in","r",stdin);
// freopen("walk.out","w",stdout);
int t=1;
// cin>>t;
while(t--) solve();
}
