#include <bits/stdc++.h>
using namespace std;
using ll = long long;
struct dsu {
vector<int> par, siz;
dsu(int n) {
par.resize(n);
siz.resize(n+1, 1);
iota(par.begin(), par.end(), 0);
}
int holvan(int u) {
return par[u] == u ? u : par[u] = holvan(par[u]);
}
bool unio(int u, int v) {
u = holvan(u); v = holvan(v);
if (u == v) return false;
if (siz[u] > siz[v]) swap(u, v);
siz[v] += siz[u];
par[u] = v;
return true;
}
};
void solve() {
int n; cin >> n;
vector<int> v(n);
for (int i = 0; i < n; i++) cin >> v[i];
sort(v.begin(), v.end());
v.erase(unique(v.begin(), v.end()), v.end());
int m = v.size();
vector<array<int, 3>> edges;
for (int i = 0; i < m; i++) {
for (int j = v[i]; j <= 500'000; j+=v[i]) {
auto it = lower_bound(v.begin(), v.end(), j);
if (it != v.end()) {
edges.push_back({(*it)-j, (int)(it-v.begin()), i});
it++;
if (it != v.end()) edges.push_back({(*it)-j, (int)(it-v.begin()), i});
} else break;
}
}
sort(edges.begin(), edges.end());
ll ans = 0;
dsu d(m);
for (auto [w, u, v] : edges) {
if (d.unio(u, v)) ans += w;
}
cout << ans << "\n";
}
int main() {
ios::sync_with_stdio(0); cin.tie(0);
int t = 1;
// cin >> t;
while (t--) solve();
return 0;
}
