#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
/* DEFINES */
#define F first
#define S second
#define ll long long
#define ull unsigned long long
#define ld long double
#define npos ULLONG_MAX
#define INF LLONG_MAX
#define vv(a) vector<a>
#define pp(a, b) pair<a, b>
#define pq(a) priority_queue<a>
#define qq(a) queue<a>
#define ss(a) set<a>
#define mm(a, b) map<a, b>
#define ump(a, b) unordered_map<a, b>
#define sync \
ios_base::sync_with_stdio(0); \
cin.tie(0); \
cout.tie(0);
#define elif else if
#define endl "\n"
#define allc(a) begin(a), end(a)
#define all(a) a, a + sizeof(a) / sizeof(a[0])
#define pb push_back
#define logi(a) __lg(a)
#define sqrt(a) sqrtl(a)
#define mpr make_pair
#define ins insert
using namespace std;
using namespace __gnu_pbds;
using namespace __cxx11;
typedef char chr;
typedef basic_string<chr> str;
template <typename T, typename key = less<T>>
using ordered_set = tree<T, null_type, key, rb_tree_tag, tree_order_statistics_node_update>;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
const ll sz = 1e5 + 5;
ll dsu[sz];
ll repr(ll x)
{
if (dsu[x] < 0)
return x;
return dsu[x] = repr(dsu[x]);
}
bool Union(ll x, ll y)
{
x = repr(x);
y = repr(y);
if (x == y)
return false;
if (dsu[x] < dsu[y])
swap(dsu[x], dsu[y]);
dsu[y] += dsu[x];
dsu[x] = y;
return true;
}
struct edge
{
ll a, b, c;
};
void solve()
{
ll n;
cin >> n;
for (ll i = 1; i <= n; i++)
dsu[i] = -1;
ll a[n + 1];
for (ll i = 1; i <= n; i++)
cin >> a[i];
ll ans = 0;
if (n == 1)
{
cout << "0\n";
return;
}
edge e[n * (n - 1) / 2];
ll ptr = 0;
for (ll i = 1; i <= n; i++)
for (ll j = i + 1; j <= n; j++)
e[ptr++] = {i, j, min(a[j] % a[i], a[i] % a[j])};
sort(all(e),
[](edge a, edge b)
{
return a.c < b.c;
});
for (ll i = 0; i < n * (n - 1) / 2; i++)
if (Union(e[i].a, e[i].b))
ans += e[i].c;
cout << ans << endl;
}
/*
*/
int main()
{
sync
// precomp();
ll t = 1;
// cin >> t;
for (ll i = 1; i <= t; i++)
// cout << "Case " << i << ": ",
solve();
cerr << "\nTime elapsed : " << clock() * 1000.0 / CLOCKS_PER_SEC << " ms\n";
}
