#include<bits/stdc++.h>
#define int long long
using namespace std;

const int MAXN = 1e7 + 10;
const int mod = 998244353;

int n, k;
int dp[MAXN], sum[MAXN];
int fac[MAXN], inv[MAXN];

int qpow(int a, int b){ int res = 1; for(; b; b >>= 1, a = a * a % mod) if(b & 1) res = res * a % mod; return res; }

signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	
	cin >> n >> k; dp[0] = sum[0] = 1;
	fac[0] = 1; for(int i = 1; i <= n; ++i) fac[i] = fac[i - 1] * i % mod;
	inv[n] = qpow(fac[n], mod - 2); for(int i = n - 1; i >= 0; --i) inv[i] = inv[i + 1] * (i + 1) % mod;
	for(int i = 1; i <= n; ++i){
		dp[i] = fac[i - 1] * (sum[i - 1] - (i <= k ? 0ll : sum[i - min(k, i) - 1]) + mod) % mod;
		sum[i] = (sum[i - 1] + dp[i] * inv[i] % mod) % mod;
	}
	cout << dp[n];
	
	return 0;
}