#include<bits/stdc++.h>
using namespace std;
using ll = int;
const ll N = 1e7 + 2;
ll a[100005];
ll ataman[100005];
ll Get(ll x) {
if (x == ataman[x]) return x;
return ataman[x] = Get(ataman[x]);
}
void Unite(ll x, ll y) {
x = Get(x);
y = Get(y);
if ( x == y) return ;
if ( x > y) swap(x, y);
ataman[y] = x;
}
int main() {
ll n, m, r, x, y, i, j, ans, t;
cin >> n;
set < ll > S;
for (i = 1; i <= n; i ++) {
cin >> x;
S.insert(x);
}
n = S.size();
r = 1;
for (ll X : S) {
a[r] = X;
r ++;
}
vector < pair < ll, pair < ll, ll > > > v;
for (i = 1; i <= n; i ++) {
for ( j = 2 * a[i]; j <= a[n]; j += a[i]) {
r = lower_bound(a + 1, a + n + 1, j) - a;
if ( r> n) break;
if ( !v.empty() && v.back().second.second == r) {
v.pop_back();
}
v.push_back(make_pair(a[r] - j, make_pair(i, r)));
}
}
for (i = 1; i < n; i ++) {
v.push_back(make_pair(a[i + 1] %a[i],make_pair(i , i + 1) ));
}
for (i = 1; i <= n; i ++) ataman[i] = i;
ans = 0;
sort(v.begin(), v.end());
for (i = 0; i < v.size(); i ++) {
x = v[i].second.first;
y = v[i].second.second;
x = Get(x);
y = Get(y);
if ( x != y) {
Unite(x, y);
ans += v[i].first;
}
}
cout << ans << endl;
}
