#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
//using mint = modint1000000007;
//const int mod = 1000000007;
using mint = modint998244353;
const int mod = 998244353;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n) - 1; i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r) - 1;i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }

int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n, m, k; cin >> n >> m >> k;
	vector<int>cnt(n + 1);
	map<int, int>mp;
	rep(i, m) {
		int a; cin >> a;
		mp[a]++;
	}
	for (auto[k, v] : mp) {
		for (int i = k; i <= n; i += k) {
			cnt[i] += v;
		}
	}
	mint ans = 0;
	mint invM = mint::raw(m).inv();
	rep2(i, 1, n + 1) {
		mint p = (m - cnt[i]) * invM;
		ans += (mint)1 - p.pow(k);
	}
	cout << ans.val() << endl;
	return 0;
}