#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define all(V) V.begin(),V.end()
#define MOD 998244353

ll tr[1000005], A[200010], g[1000005];

ll modpow(ll x, ll y) {
	ll ans = 1;
	while (y) {
		if (y & 1)ans *= x;
		x *= x;
		ans %= MOD;
		x %= MOD;
		y /= 2;
	}
	return ans;
}

int main() {
	for (int i = 1;i <= 1000000;i++) {
		tr[i] = 0;
		g[i] = 0;
	}
	for (ll i = 2;i <= 1000000;i++) {
		tr[i] -= 1 - modpow(i, MOD - 2);
		for (ll j = i * 2;j <= 1000000;j += i) {
			tr[j] -= tr[i];
			tr[j] %= MOD;
		}
	}
	int N;
	cin >> N;

	ll as = 0;
	for (int i = 0;i < N;i++) {
		cin >> A[i];
		g[A[i]] += A[i];
		g[A[i]] %= MOD;
		as += A[i];
		as %= MOD;
	}

	for (int i = 2;i <= 1000000;i++) {
		for (int j = i * 2;j <= 1000000;j += i) {
			g[i] += g[j];
			g[i] %= MOD;
		}
	}

	ll ans = as * as % MOD;
	for (int i = 2;i <= 1000000;i++) {
		ans += g[i] * g[i] % MOD * tr[i] % MOD;
		ans %= MOD;if (ans < 0)ans += MOD;
	}
	ans -= as;
	if (ans < 0)ans += MOD;
	if (ans & 1)ans = (ans + MOD) / 2;
	else ans /= 2;
	cout << ans % MOD << endl;
}