#include<bits/stdc++.h>
#define int long long
#define mod 998244353ll
#define pii pair<int,int>
#define fi first
#define se second
#define mems(x,y) memset(x,y,sizeof(x))
#define pb push_back
#define db double
using namespace std;
const int maxn=10000010;
const int inf=1e18;
inline int read(){
	int x=0,f=1;
	char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
	while(ch>='0'&&ch<='9'){x=(x<<3)+(x<<1)+(ch-48);ch=getchar();}
	return x*f;
}
bool Mbe;

int n,k,sum;
int dp[maxn];
int fac[maxn],inv[maxn],ni[maxn];
inline int ksm(int a,int b=mod-2){
	int ans=1;
	while(b){
		if(b&1)ans=ans*a%mod;
		a=a*a%mod;
		b>>=1;
	}
	return ans;
}
int C(int m,int n){
	if(m<n||m<0||n<0)return 0;
	return fac[m]*inv[n]%mod*inv[m-n]%mod;
}
void work(){
	n=read(),k=read();
	fac[0]=1;for(int i=1;i<=n;i++)fac[i]=fac[i-1]*i%mod;
	inv[n]=ksm(fac[n]);for(int i=n-1;~i;i--)inv[i]=inv[i+1]*(i+1)%mod;
	for(int i=1;i<=n;i++)ni[i]=fac[i-1]*inv[i]%mod;
	dp[0]=1;sum=fac[n-1];
	for(int i=1;i<=n;i++){
		if(i>=k){
			(sum+=mod-dp[i-k-1]*fac[n-(i-k-1)-1]%mod)%=mod;
		}
		dp[i]=sum*inv[n-i]%mod;
		(sum+=dp[i]*fac[n-i-1])%=mod;
	}
	printf("%lld\n",dp[n]);
}

// \
444

bool Med;
int T;
signed main(){
	// freopen("b.in","r",stdin);
	// freopen("b.out","w",stdout);
	
//	ios::sync_with_stdio(0);
//	cin.tie(0);cout.tie(0);
	
//	cerr<<(&Mbe-&Med)/1048576.0<<" MB\n";
	
	T=1;
	while(T--)work();
}