#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define int long long
#define pii pair<ll, ll>
#define fi first
#define se second
const ll N = 1e5 + 5, inf = 1e18, mod = 1e9 + 7, block = 320, lim = 16;
int n;
vector <int> a;
int par[N], sz[N];
int fre[10000005];
void makeset() {
for (int i = 1; i <= n; i++) {
par[i] = i;
sz[i] = 1;
}
}
int find(int u) {
if (u == par[u]) return u;
return par[u] = find(par[u]);
}
void join(int u, int v) {
u = find(u), v = find(v);
if (u != v) {
if (sz[u] < sz[v]) swap(u, v);
sz[u] += sz[v];
par[v] = u;
}
}
struct item {
int u, v, w;
};
vector<item> edge;
bool cmp(item a, item b) {
return a.w < b.w;
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n;
a.assign(n + 5, 0);
for (int i = 1; i <= n; i++) cin >> a[i];
sort(a.begin(), a.end());
a.erase(unique(a.begin(), a.end()), a.end());
n = (int)a.size() - 1;
if (n <= 1) {
cout << 0;
return 0;
}
int maxA = a[n];
vector<int> cnt(maxA + 1, 0);
for (int i = 1; i <= n; i++) {
for (int mul = a[i]; mul <= maxA; mul += a[i]) {
int pos;
if (mul == a[i]) pos = upper_bound(a.begin() + 1, a.begin() + n + 1, mul) - a.begin();
else pos = lower_bound(a.begin() + 1, a.begin() + n + 1, mul) - a.begin();
if (pos <= n) {
int w = (int)(a[pos] % a[i]);
cnt[w]++;
}
}
}
long long total = 0;
vector<int> start(maxA + 2, 0);
for (int w = 0; w <= maxA; w++) {
start[w] = (int)total;
total += cnt[w];
}
if (total == 0) {
cout << 0;
return 0;
}
vector<int32_t> eu((size_t)total), ev((size_t)total);
for (int w = 0; w <= maxA; w++) cnt[w] = 0;
for (int i = 1; i <= n; i++) {
for (int mul = a[i]; mul <= maxA; mul += a[i]) {
int pos;
if (mul == a[i]) pos = upper_bound(a.begin() + 1, a.begin() + n + 1, mul) - a.begin();
else pos = lower_bound(a.begin() + 1, a.begin() + n + 1, mul) - a.begin();
if (pos <= n) {
int w = (int)(a[pos] % a[i]);
int p = start[w] + cnt[w];
eu[p] = (int32_t)i;
ev[p] = (int32_t)pos;
cnt[w]++;
}
}
}
makeset();
long long ans = 0;
for (int w = 0; w <= maxA; w++) {
int s = start[w];
int e = (w == maxA ? (int)total : start[w + 1]);
for (int i = s; i < e; i++) {
int u = eu[i], v = ev[i];
if (find(u) != find(v)) {
join(u, v);
ans += w;
}
}
}
cout << ans;
return 0;
}
