#include <bits/stdc++.h>
using namespace std;
using namespace chrono;
#if __has_include(<atcoder/all>)
#include <atcoder/all>
using namespace atcoder;
#endif

int main()
{
    int64_t n, m, k;
    cin >> n >> m >> k;
    vector<int64_t> as(m);
    for (auto &&a : as)
    {
        cin >> a;
    }

    vector<int64_t> cnt(1000001);
    for (auto &&a : as)
    {
        for (int64_t i = a; i <= 1000000; i += a)
        {
            cnt[i]++;
        }
    }

    using mint = modint998244353;

    mint ans = 0;

    for (int64_t i = 1; i <= n; i++)
    {
        ans += 1 - (mint(m - cnt[i]) / m).pow(k);
    }

    cout << ans.val() << endl;

    return 0;
}