#define MD 998244353
ll@N,@M,@K,@A[M];
Mint ans = 0;
ll cnt[N+1];
rep(i,N+1)cnt[i]=0;
sort(A,A+M);
for(int it = 0; it < M; ) {
    int j = it;
    while(j < M && A[it] == A[j]) j++;
    rep(k, A[it], N + 1, A[it]) cnt[k] += j - it;
    it = j;
}
rep(i, 1, N+1) {
    ans += 1;
    Mint t = M-cnt[i];
    Mint s = M;
    ans -= (t/s).pw(K);
}
wt(ans);