// Author: 4uckd3v - Nguyen Cao Duc
#include <bits/stdc++.h>
using namespace std;
#define all(x) (x).begin(), (x).end()
typedef long long ll;
const int MAX_N = 1e5;
const int MAX_V = 1e7;
const int MOD = 1e9 + 7;
struct Edge {
int u, v, w;
Edge() {};
Edge(int u, int v, int w) : u(u), v(v), w(w) {};
bool operator<(const Edge &other) const {
return w < other.w;
};
};
struct DSU {
vector<int> par, sz;
int n;
DSU(int n) : n(n) {
par.resize(n + 1), sz.resize(n + 1);
for (int u = 1; u <= n; u++) {
par[u] = u;
sz[u] = 1;
};
};
int findSet(int u) {
return u == par[u] ? u : par[u] = findSet(par[u]);
};
bool unionSet(int u, int v) {
u = findSet(u), v = findSet(v);
if (u == v) return false;
if (sz[u] < sz[v]) swap(u, v);
par[v] = u;
sz[u] += sz[v];
return true;
};
};
int n;
int a[MAX_N + 5];
namespace SUBTASK_1 {
const int N = 1000;
void Solve() {
DSU DSU(n);
vector<Edge> edges;
for (int i = 1; i <= n; i++) {
for (int j = i + 1; j <= n; j++) {
edges.push_back(Edge(i, j, min(a[i] % a[j], a[j] % a[i])));
};
};
sort(all(edges));
ll res = 0;
for (Edge &e : edges) {
int u = e.u, v = e.v, w = e.w;
if (DSU.unionSet(u, v)) res += w;
};
cout << res << '\n';
};
}; // namespace SUBTASK_1
namespace SUBTASK_2 {
const int N = MAX_N;
const int V = MAX_V;
int idx[V + 5], nextExist[V + 5];
bool used[N + 5];
void Solve() {
sort(a + 1, a + n + 1);
DSU DSU(n);
int numCC = n;
for (int i = 1; i <= n; i++) {
idx[a[i]] = i;
if (a[i] == a[i - 1]) numCC -= DSU.unionSet(i, i - 1);
};
int mx = a[n];
for (int i = 1; i <= mx; i++) {
if (!idx[i]) continue;
for (int j = 2 * i; j <= mx; j += i) {
if (idx[j]) {
numCC -= DSU.unionSet(idx[i], idx[j]);
idx[j] = idx[i];
};
};
};
if (numCC == 1) {
return cout << 0, void();
};
nextExist[mx + 1] = mx + 1;
for (int i = mx; i >= 1; i--) {
nextExist[i] = nextExist[i + 1];
if (idx[i]) nextExist[i] = i;
};
vector<Edge> edges;
for (int i = 1; i <= mx; i++) {
if (!idx[i]) continue;
int u = idx[i];
for (int j = i; j <= mx; j += i) {
int l = j + 1, r = min(j + i - 1, mx);
if (nextExist[l] <= r) {
int v = idx[nextExist[l]];
edges.push_back(Edge(u, v, nextExist[l] - j));
};
};
};
sort(all(edges));
ll res = 0;
for (Edge &e : edges) {
int u = e.u, v = e.v, w = e.w;
if (DSU.unionSet(u, v)) res += w, numCC--;
if (numCC == 1) break;
};
cout << res << '\n';
};
}; // namespace SUBTASK_2
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
if (fopen("SIRNI.INP", "r")) {
freopen("SIRNI.INP", "r", stdin);
freopen("SIRNI.OUT", "w", stdout);
};
cin >> n;
for (int i = 1; i <= n; i++) {
cin >> a[i];
};
if (n <= 1000)
return SUBTASK_1::Solve(), 0;
SUBTASK_2::Solve();
};
