#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>
/*#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")*/

using namespace __gnu_pbds;
using namespace std;


#define ll long long
#define ld long double
#define mp make_pair
#define what_is(x) cerr << #x << " is " << x << endl;

typedef tree<
        int,
        null_type,
        less<int>,
        rb_tree_tag,
        tree_order_statistics_node_update>
        ordered_set;


int p = 998244353;


int mul(int a, int b) {
    if (a<0) a+=p;
    if (b<0) b+=p;
    return (1LL * a * b) % p;
}

int add(int a, int b) {
    int s = (a+b);
    if (s>=p) s-=p;
    return s;
}

int sub(int a, int b) {
    int s = (a+p-b);
    if (s>=p) s-=p;
    return s;
}

int po(int a, int deg)
{
    if (deg==0) return 1;
    if (deg%2==1) return mul(a, po(a, deg-1));
    int t = po(a, deg/2);
    return mul(t, t);
}

int inv(int n)
{
    return po(n, p-2);
}


vector<int> Z(vector<int> s)
{
    int n = s.size();
    vector<int> z(n);
    int L = 0, R = 0;
    for (int i = 1; i < n; i++) {
        if (i > R) {
            L = R = i;
            while (R < n && s[R-L] == s[R]) R++;
            z[i] = R-L; R--;
        } else {
            int k = i-L;
            if (z[k] < R-i+1) z[i] = z[k];
            else {
                L = i;
                while (R < n && s[R-L] == s[R]) R++;
                z[i] = R-L; R--;
            }
        }
    }
    return z;
}

mt19937 rnd(time(0));
/*
struct Line {
    mutable ll k, m, p;
    bool operator<(const Line& o) const { return k < o.k; }
    bool operator<(ll x) const { return p < x; }
};

struct CHT : multiset<Line, less<>> {
    // (for doubles, use inf = 1/.0, div(a,b) = a/b)
    const ll inf = LLONG_MAX;
    ll div(ll a, ll b) { // floored division
        return a /b - ((a ^ b) < 0 && a % b); }
    bool isect(iterator x, iterator y) {
        if (y == end()) { x->p = inf; return false; }
        if (x->k == y->k) x->p = x->m > y->m ? inf : -inf;
        else x->p = div(y->m - x->m, x->k - y->k);
        return x->p >= y->p;
    }
    void add(ll k, ll m) {
        auto z = insert({k, m, 0}), y = z++, x = y;
        while (isect(y, z)) z = erase(z);
        if (x != begin() && isect(--x, y)) isect(x, y = erase(y));
        while ((y = x) != begin() && (--x)->p >= y->p)
        isect(x, erase(y));
    }
    ll query(ll x) {
        assert(!empty());
        auto l = *lower_bound(x);
        return l.k * x + l.m;
    }
};
*/

const int N = 1000005;
vector<vector<int>> d(N);
vector<int> phi(N);
vector<int> min_prime(N);
vector<bool> check(N);

void init()
{
//    for (int i = 1; i<N; i++)
  //      for (int j = i; j<N; j+=i) d[j].push_back(i);
    for (int i = 2; i<N; i++) if (!check[i])
    {
        min_prime[i] = i;
        if (i<=N/i) for (int j = i*i; j<N; j+=i) if (min_prime[j]==0) {min_prime[j] = i; check[j] = true;}
    }
    phi[1] = 1;
    for (int i = 2; i<N; i++)
    {
        int q = min_prime[i];
        if ((i/q)%q==0) phi[i] = phi[i/q];
        else phi[i] = phi[i/q]*(1-q);
    }

}

vector<int> sum(N);
vector<int> sum_sq(N);

int inv2 = inv(2);

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr);

    init();
    int n;
    cin >> n;
    vector<int> a(n);
    for (int i = 0; i < n; i++) cin >> a[i];
    for (int i = 0; i < n; i++) {
        for (int it = 1; it*it<=a[i]; it++) if (a[i]%it==0) {
            sum[it] = add(sum[it], a[i]/it);
            sum_sq[it] = add(sum_sq[it], mul(a[i], a[i]/it));
            if (it*it!=a[i])
            {
              int it1 = a[i]/it;  
              sum[it1] = add(sum[it1], a[i]/it1);
            	sum_sq[it1] = add(sum_sq[it1], mul(a[i], a[i]/it1));
            }
        }
    }

    /*for (int i =  1; i<10; i++) {
        cout<<i<<": "<<phi[i]<<' '<<sum[i]<<' '<<sum_sq[i]<<endl;
        for (auto it: d[i]) cout<<it<<' ';
        cout<<endl;
    }*/





    int total = 0;
    for (int i = 1; i < N; i++)
    {
        int prod_sum = mul(inv2, sub(mul(i, mul(sum[i], sum[i])), sum_sq[i]));
        total = add(total, mul(prod_sum, phi[i]));
    }
    cout<<total;

}

Measured memory_bytes: 42240