#include <bits/stdc++.h>
using namespace std;
#define ar array
#define ll long long
const int inf = 2e9;
const int mxN = 1e5 + 5;
const int N = 1e7 + 2;
const ll linf = 1e13;
int here[N] = {}, V[N], nxt[N];
vector<int> A;
vector<ar<int, 3>> edges;
int find(int x) {
int y = x;
while (V[x] > 0)
x = V[x];
while (x != y)
y = exchange(V[y], x);
return x;
}
int unite(int x, int y) {
x = find(x);
y = find(y);
if (x == y)
return 0;
if (V[x] > V[y])
swap(x, y);
V[x] += V[y];
V[y] = x;
return 1;
}
void solve() {
for (int i = 1; i < N;i++)
V[i] = -1, nxt[i] = -1;
int n;
cin >> n;
A.reserve(n);
for (int i = 1; i <= n;i++) {
int x; cin >> x;
here[x] = 1;
A.push_back(x);
}
sort(A.begin(), A.end());
A.erase(unique(A.begin(), A.end()), A.end());
for (int i = A.back() - 1; i > 0; i--) {
nxt[i] = nxt[i + 1];
if (here[i + 1])
nxt[i] = i + 1;
}
for (int x : A) {
for (int d = x; d < N; d += x) {
if (here[d])
unite(d, x);
if (nxt[d] == -1)
continue;
if (d + x < N && nxt[d] == nxt[d + x])
continue;
int y = nxt[d];
edges.push_back({y - d, x, y});
}
}
sort(edges.begin(), edges.end());
ll ans = 0;
for (auto [w, x, y] : edges) {
if (unite(x, y))
ans += w;
}
cout << ans;
}
int32_t main() {
#ifdef Behruz
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios :: sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
solve();
return 0;
}
