#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using pl = pair<ll,ll>;
using pii = pair<int,int>;
using tpl = tuple<int,int,int>;
#define all(a) a.begin(), a.end()
#define filter(a) a.erase(unique(all(a)), a.end())
struct DSU {
vector<int> lab;
DSU (int sz) : lab(sz + 1, -1) {}
int get (int u) {
if (lab[u] < 0) return u;
return lab[u] = get(lab[u]);
}
bool unite (int a, int b) {
a = get(a), b = get(b);
if (a == b) return 0;
if (-lab[a] < -lab[b]) swap(a, b);
lab[a] += lab[b], lab[b] = a;
return 1;
}
};
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
/// read input & refine
int n; cin >> n;
vector<int> a(n);
for (int &u : a) cin >> u;
sort(all(a)), filter(a), n = a.size();
int mx = *max_element(all(a));
/// edge case
if (a[0] == 1) return cout << 0, 0;
/// generate potential edges
vector<tpl> edges;
for (int i = 0; i < n; i++) {
for (int mult = 1; 1LL * a[i] * mult <= mx; mult++) {
// build edge
int nxt = lower_bound(all(a), max(a[i] + 1, a[i] * mult)) - a.begin();
if (nxt < n) {
mult = a[nxt] / a[i];
edges.emplace_back(a[nxt] - a[i] * mult, i, nxt);
}
}
}
sort(all(edges));
/// build MST using Kruskal algorithm
DSU dsu(n); ll ans = 0;
for (tpl iter : edges) {
int weight, a, b; tie(weight, a, b) = iter;
if (dsu.unite(a, b)) ans += weight;
}
cout << ans;
return 0;
}
