#include <iostream>
#include <algorithm>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <numeric>
#include <bitset>
#include <cmath>

static const int MOD = 1000000007;
using ll = long long;
using u32 = unsigned;
using u64 = unsigned long long;
using namespace std;

template<class T> constexpr T INF = ::numeric_limits<T>::max()/32*15+208;

int main() {
    int n;
    cin >> n;
    vector<int> v(n);
    int M = 400000;
    vector<int> cnt(M+1);
    for (auto &&i : v) scanf("%d", &i), cnt[i]++;
    vector<ll> sum(M+2), cnts(M+2);
    for (int i = 0; i <= M; ++i) {
        sum[i+1] = sum[i] + (ll)cnt[i]*i;
        cnts[i+1] = cnts[i] + cnt[i];
    }
    ll ans = 0;
    for (int i = 2; i <= M; ++i) {
        for (int j = 0; j <= M; j += i) {
            int k = min(M+1, j+i);
            ans += (sum[k]-sum[j]-(cnts[k]-cnts[j])*j)*cnt[i];
        }
    }
    cout << ans << "\n";
    return 0;
}