#include<bits/stdc++.h>
using namespace std;
const int mod=998244353,maxn=1e7+5,M=100005;
#define int long long
#define pb push_back
inline int read(){
	char ch=getchar();int x=0;bool f=0;
	for(;!isdigit(ch);ch=getchar())if(ch=='-')f=1;
	for(;isdigit(ch);ch=getchar())x=(x<<1)+(x<<3)+(ch^48);
	if(f==1)x=-x;return x;
}
int f[maxn],n,k,sum=0,inv[maxn],res;
signed main(){
	n=read(),k=read();
	f[0]=1;res=1;inv[0]=inv[1]=1;sum=1;
    for(int i=2;i<=n;i++)inv[i]=(mod-mod/i)*inv[mod%i]%mod;
	for(int i=1;i<=n;i++){
        f[i]=sum;
        res=res*i%mod;
        if(i>=k)res=res*inv[i-k]%mod;
        sum=sum*i%mod;sum=sum+f[i];sum%=mod;
        if(i>=k)sum=sum-f[i-k]*res%mod;
        sum=sum+mod;sum%=mod;
        //cout<<f[i]<<" "<<sum<<" "<<res<<endl;
	}
	cout<<f[n]<<endl;
	return 0;
}