#include <bits/stdc++.h>
using namespace std;
struct Edge {
int u, v;
int w;
Edge(int _u, int _v, int _w): u(_u), v(_v), w(_w) {}
Edge(): u(0), v(0), w(0) {}
bool operator<(Edge const& o) const { return w < o.w; }
} e[40000007];
struct DSU {
vector<int> par, rank;
DSU(int n): par(n+1), rank(n+1) {}
void make_set(int u) {
par[u] = u;
rank[u] = 0;
}
int find_set(int v) {
return par[v] == v ? v : par[v] = find_set(par[v]);
}
bool union_set(int u, int v) {
u = find_set(u);
v = find_set(v);
if (u != v) {
if (rank[u] < rank[v]) swap(u, v);
par[v] = u;
if (rank[u] == rank[v]) rank[u]++;
return true;
}
return false;
}
};
int n;
vector<int> p;
int nxt[10000005], m = 0;
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n;
p.resize(n);
for (int i = 0; i < n; i++) cin >> p[i];
sort(p.begin(), p.end());
p.erase(unique(p.begin(), p.end()), p.end());
n = p.size();
for (int i = 0; i < n - 1; i++) {
nxt[p[i]] = i;
for (int j = p[i] + 1; j < p[i + 1]; j++) nxt[j] = i + 1;
}
nxt[p[n - 1]] = n - 1;
int mx = p[n - 1];
int maxWeight = 0;
for (int i = 0; i < n; i++) {
int w1 = p[nxt[p[i]+1]] % p[i];
e[++m] = {i, nxt[p[i]+1], w1};
maxWeight = max(maxWeight, w1);
for (int j = p[i]; j <= mx; ) {
int v = nxt[j];
int w2 = p[v] % p[i];
e[++m] = {i, v, w2};
maxWeight = max(maxWeight, w2);
if (p[v] / p[i] == 0) break;
j = (p[v] / p[i]) * p[i] + p[i];
}
}
// -------------------- COUNTING SORT --------------------
vector<vector<Edge>> bucket(maxWeight + 1);
for (int i = 1; i <= m; ++i)
bucket[e[i].w].push_back(e[i]);
int idx = 1;
for (int w = 0; w <= maxWeight; ++w)
for (Edge &edge : bucket[w])
e[idx++] = edge;
// -------------------------------------------------------
DSU d(n);
for (int i = 1; i <= n; i++) d.make_set(i);
int total = 0, dem = 0;
for (int i = 1; i <= m; i++) {
auto [u, v, w] = e[i];
if (d.union_set(u, v)) {
total += w;
if (++dem == n - 1) break;
}
}
cout << total;
}
