#include <bits/stdc++.h>
#define ll long long
using namespace std;
#define f first
#define s second
#define pb push_back
#define ep emplace
#define eb emplace_back
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define uniquev(v) sort(all(v)), (v).resize(unique(all(v)) - (v).begin())
#define mem(f,x) memset(f , x , sizeof(f))
#define sz(x) (int)(x).size()
#define __lcm(a, b) (1ll * ((a) / __gcd((a), (b))) * (b))
#define mxx *max_element
#define mnn *min_element
#define cntbit(x) __builtin_popcountll(x)
#define len(x) (int)(x.length())
const int N = 2e5 + 10;
const int M = 1e7 + 10;
vector <pair <int, int>> save[M + 1];
int a[N], pos[N], p[N], sz[N], mx[M + 1];
int get(int a) {
return p[a] ? get(p[a]) : a;
}
bool unite(int a, int b) {
a = get(a), b = get(b);
if (a == b)
return 0;
if (sz[a] < sz[b])
swap(a, b);
sz[a] += sz[b];
p[b] = a;
return 1;
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n;
cin >> n;
for (int i = 1; i <= n; i++) {
sz[i] = 1;
cin >> a[i];
mx[a[i]] = i;
}
if (a[mx[1]] == 1) {
cout << 0 << '\n';
return 0;
}
for (int i = M - 2; i >= 0; i--) {
if (mx[i] == 0) {
mx[i] = mx[i + 1];
}
}
for (int i = 2; i < M; i++) {
if (i == a[mx[i]]) {
int j = i * 2, p = mx[i];
while (j < M) {
int nxt = mx[j];
if (nxt == 0)
break;
save[a[nxt] % i].pb({p, nxt});
j = (a[nxt] / i + 1) * i;
}
if (mx[i + 1]) {
save[a[mx[i + 1]] % i].pb({p, mx[i + 1]});
}
}
}
ll ans = 0;
for (int i = 0; i < M; i++) {
for (auto x : save[i]) {
if (unite(x.f, x.s))
ans += i;
}
}
cout << ans << '\n';
return 0;
}
