#include <bits/stdc++.h>

#define FOR(i, a, b) for(ll i = (a); i < (b); i++)
#define REP(i, a) FOR(i, 0, a)

using namespace std;
using ll = long long;

const ll MOD = 998244353;
struct mll{
    ll x;
    mll(ll _x = 0){
        x = (_x % MOD + MOD) % MOD;
    }
};
ostream& operator<<(ostream &os, mll n){
    os << n.x;
    return os;
}

mll operator +(mll a, mll b){
    return mll(a.x + b.x);
}
mll operator -(mll a, mll b) {
    return mll(a.x - b.x);
}
void operator +=(mll &a, mll b) {
    a = a + b;
}
mll operator *(mll a, mll b){
    return mll(a.x * b.x);
}
void operator *=(mll &a, mll b){
    a = a * b;
}
mll mpw(mll n, ll m){
    if(m < 0){
        n = mpw(n, MOD - 2);
        m *= -1;
    }
    mll ret(1), p = n;
    while(m){
        if(m & 1){
            ret *= p;
        }
        p *= p;
        m >>= 1;
    }
    return ret;
}
mll minv(mll n){
    return mpw(n, -1);
}
mll operator /(mll a, mll b){
    return a * minv(b);
}

int main(){
    ll X = 178;
    ll N, M, K;
    scanf("%lld %lld %lld", &N, &M, &K);
    vector<ll> cnt_A(X + 1, 0), cnt(N + 1, 0);
    REP(i, M) {
        ll a;
        scanf("%lld", &a);
        if (a <= X) {
            ++cnt_A[a];
        } else {
            for (ll j = a; j <= N; j += a) {
                ++cnt[j];
            }
        }
    }

    mll ans(0), minv_M = minv(M);
    FOR(i, 1, N + 1) {
        ll m = cnt[i];
        for (ll j = 1; j <= X && j * j <= i; ++j) {
            if (i % j == 0) {
                m += cnt_A[j];
                ll j2 = i / j;
                if (j2 <= X && j2 != j){
                    m += cnt_A[j2];
                }
            }
        }
        ans += mll(1) - mpw(mll(1) - mll(m) * minv_M, K);
    }
    printf("%lld\n", ans.x);
}