#include <bits/stdc++.h> 

using i64 = long long; 
using u64 = unsigned long long; 
using u32 = unsigned; 

using u128 = unsigned __int128; 
using i128 = __int128; 

template<class T>
constexpr T power(T a, i64 b) {
    T res {1};
    for (; b; b /= 2, a *= a) {
        if (b % 2) {
            res *= a;
        }
    }
    return res;
}

constexpr i64 mul(i64 a, i64 b, i64 p) {
    i64 res = a * b - i64(1.L * a * b / p) * p;
    res %= p;
    if (res < 0) {
        res += p;
    }
    return res;
}

template<i64 P>
struct MInt {
    i64 x;
    constexpr MInt() : x {0} {}
    constexpr MInt(i64 x) : x {norm(x % getMod())} {}
    
    static i64 Mod;
    constexpr static i64 getMod() {
        if (P > 0) {
            return P;
        } else {
            return Mod;
        }
    }
    constexpr static void setMod(i64 Mod_) {
        Mod = Mod_;
    }
    constexpr i64 norm(i64 x) const {
        if (x < 0) {
            x += getMod();
        }
        if (x >= getMod()) {
            x -= getMod();
        }
        return x;
    }
    constexpr i64 val() const {
        return x;
    }
    constexpr MInt operator-() const {
        MInt res;
        res.x = norm(getMod() - x);
        return res;
    }
    constexpr MInt inv() const {
        return power(*this, getMod() - 2);
    }
    constexpr MInt &operator*=(MInt rhs) & {
        if (getMod() < (1ULL << 31)) {
            x = x * rhs.x % int(getMod());
        } else {
            x = mul(x, rhs.x, getMod());
        }
        return *this;
    }
    constexpr MInt &operator+=(MInt rhs) & {
        x = norm(x + rhs.x);
        return *this;
    }
    constexpr MInt &operator-=(MInt rhs) & {
        x = norm(x - rhs.x);
        return *this;
    }
    constexpr MInt &operator/=(MInt rhs) & {
        return *this *= rhs.inv();
    }
    friend constexpr MInt operator*(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res *= rhs;
        return res;
    }
    friend constexpr MInt operator+(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res += rhs;
        return res;
    }
    friend constexpr MInt operator-(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res -= rhs;
        return res;
    }
    friend constexpr MInt operator/(MInt lhs, MInt rhs) {
        MInt res = lhs;
        res /= rhs;
        return res;
    }
    friend constexpr std::istream &operator>>(std::istream &is, MInt &a) {
        i64 v;
        is >> v;
        a = MInt(v);
        return is;
    }
    friend constexpr std::ostream &operator<<(std::ostream &os, const MInt &a) {
        return os << a.val();
    }
    friend constexpr bool operator==(MInt lhs, MInt rhs) {
        return lhs.val() == rhs.val();
    }
    friend constexpr bool operator!=(MInt lhs, MInt rhs) {
        return lhs.val() != rhs.val();
    }
    friend constexpr bool operator<(MInt lhs, MInt rhs) {
        return lhs.val() < rhs.val();
    }
};

constexpr i64 MOD = 998244353;

using Z = MInt<MOD>;

void solve() {
	int N, M, K; std::cin >> N >> M >> K;

	std::vector<int> cnt(N + 1);
	for(int i = 0; i < M; i ++) {
		int z; std::cin >> z;
		if(z <= N) cnt[z] ++;
	}

	for(int i = N; i >= 1; i --) {
		for(int j = 2 * i; j <= N; j += i) {
			cnt[j] += cnt[i];
		}
	}

	Z ans = N;
	Z inv = Z(1) / Z(M);
	for(int i = 1; i <= N; i ++) {
		ans -= power(Z(M - cnt[i]) * inv, K);
	}

	std::cout << ans;
} 

int main() { 
	std::ios::sync_with_stdio(false); 
	std::cin.tie(nullptr); 

	int T = 1; 
	//std::cin >> T; 

	while (T--) { 
		solve(); 
	} 
	return 0; 
}