#include <bits/stdc++.h>
#include <iostream>
#include <cmath>
#include <vector>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <stack>
#include <algorithm>
#include <string>
#include <queue>
#include <cctype>
#include <cstring>
#include <iomanip>
#include <deque>
#include <random>
#include <sstream>
// #pragma GCC optimize("O3,unroll-loops")
// #pragma GCC target("avx,avx2,bmi,bmi2,popcnt,lzcnt")
// #pragma GCC optimize("Ofast","inline","no-stack-protector")
// #pragma GCC target("arch=skylake")
using namespace std;
#define file(name) freopen(name".inp","r",stdin);\
freopen(name".out","w",stdout);
#define TIME (1.0*clock()/CLOCKS_PER_SEC)
#define all(a) a.begin(),a.end()
#define all1(a) a+1,a+n+1
#define ll long long
const long long INF=1e18;
const long long MOD=1e9+7;
const long long MODD[] = {(long long)998244353,(long long)1e9+2277, (long long)1e9+5277}; // 998244353
const int maxN=2e5+9;
const long long LOG=19;
const double eps = 1e-1;
//------------------------
void solve();
signed main(){
ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
// file("PNUM");
int t;
// cin >> t;
t=1;
while (t--){
solve();
}
cerr << "Time: " << TIME << "s.\n";
cerr << "ducminh";
return 0;
}
/// -------------- PROBLEM SOLUION --------------------
int n;
int ans=0, ans1=0, mx=0;
// canh dscanh[10000009];
vector<pair<int,int>> dscanh[10000009];
int truoc[10000009];
// vector<int> b;
void init(int n){
for(int i=1; i<=n; i++){
truoc[i] = i;
}
}
int root(int u){
if (truoc[u]==u) return u;
return truoc[u]=root(truoc[u]);
}
bool hop(int x, int y){
int u=root(x), v=root(y);
if (u==v) return false;
truoc[v]=u;
return true;
}
void solve(){
cin >> n;
set<int> b;
for (int i=1; i<=n; i++){
int x;
cin >> x;
b.insert(x);
mx=max(mx,x);
}
// sort(all(b));
// b.resize(unique(all(b)) - b.begin());
// for(int i=0; i<b.size(); i++)
// a[i+1] = b[i];
n=b.size();
if (n == 1) return cout << 0, void();
// if (a[1] == 1) return cout << 0, void();
// sort(a+1,a+n+1);
// for (int i=2; i<=n; i++){
// ans+=min(a[1]%a[i], a[i]%a[1]);
// }
// if (n>1000) return cout << 0, void();
int ti=0;
init(mx+1);
for (int i: b) {
// for (int j=i+1; j<=n; j++) {
// int w = a[j] % a[i];
// dscanh.push_back({i, j, w});
// }
auto it=b.upper_bound(i);
if (it == b.end()) continue;
dscanh[*it-i].push_back({i,*it});
for (int m=2*i; m<=mx; m+=i){
auto it=b.lower_bound(m);
// if (it>n || it<1) continue;
// if (m==a[i] && a[it]==a[i]) it++;
// if (it>n || it<1) continue;
if (it == b.end()) continue;
// dscanh.push_back({i, it, a[it]-m});
// dscanh[ti++]={i,it,a[it]-m};
dscanh[*it%i].push_back({i,*it});
m = *it / i * i;
}
}
// sort(dscanh, dscanh+ti, cmp);
int d1=0;
for (int i=0; i<=mx; i++){
for (pair<int,int> tmp: dscanh[i]) {
if (hop(tmp.first, tmp.second)){
ans1 += i;
d1++;
if (d1==n-1) break;
}
}
}
cout << ans1;
}
