#include <bits/stdc++.h>
using namespace std; using ll = long long; using ull = unsigned long long; using i128 = __int128_t; using u128 = unsigned __int128_t; using pii = pair<int, int>;
#define rep(i, f, t, ...) for (int i = f, ##__VA_ARGS__; i <= t; ++i)
#define per(i, f, t, ...) for (int i = f, ##__VA_ARGS__; i >= t; --i)
#define eb emplace_back
#define ALL(x) x.begin(), x.end()
#define FILEIO(fn) freopen(fn".in", "r", stdin), freopen(fn".out", "w", stdout)
template < typename T > inline int SZ(T &&t) { return t.size(); }
constexpr ll mod = 998244353; inline void chkmod(ll &x) { if (x >= mod) x -= mod; } inline ll afteradd(const ll &x) { return x >= mod ? x - mod : x; } inline ll Add(const ll&x, const ll &y) { return (x + y >= mod) ? x + y - mod : x + y; }

constexpr int N = 1e7 + 5;

int n, k; ll fac[N], ifac[N], dp[N], inv[N], ans=0;

ll qpow(ll x, int y) {
	ll res = 1;
	while (y) {
		if (y & 1) {
			(res *= x) %= mod;
		}
		(x *= x) %= mod;
		y >>= 1;
	}
	return res;
}

signed main() {
	cin.tie(0)->sync_with_stdio(0);
	cin>>n>>k;fac[0]=1;rep(i,1,N-5)fac[i]=fac[i-1]*i%mod;ifac[N-5]=qpow(fac[N-5],mod-2);per(i,N-5,1)ifac[i-1]=ifac[i]*i%mod;rep(i,1,N-5)inv[i]=ifac[i]*fac[i-1]%mod;
	if(k>=n)return cout<<fac[n]<<"\n",0;dp[0]=1;rep(i,1,n-1){
		dp[i]=dp[i-1];if(i-k>=1)chkmod(dp[i]+=mod-dp[i-k-1]);(dp[i]*=inv[n-i])%=mod;
		if(i>=n-k)chkmod(ans+=fac[n-1]*dp[i]%mod);chkmod(dp[i]+=dp[i-1]);
	}cout<<ans<<"\n";return 0;
}