#include<bits/stdc++.h>
#define N 10000010
#define Pii pair<int,int>
#define Fi first
#define Se second
#define ll long long
#define ull unsigned long long
#define lb(i) i&(-i)
#define lc p<<1
#define rc p<<1|1
using namespace std;
namespace IO{
	#define SIZE (1<<21)
	#define getchar()(p1==p2&&(p2=(p1=buf)+fread(buf,1,1<<21,stdin),p1==p2)?EOF:*p1++)
	char buf[SIZE],*p1=buf,*p2=buf;
	inline bool Isdigit(char c){return c>='0'&&c<='9';}
	template <typename T>inline void read(T& r){
		r=0;bool w=0;char ch=getchar();
		while(!Isdigit(ch))w=ch=='-'?1:0,ch=getchar();
		while(Isdigit(ch))r=(r<<3)+(r<<1)+(ch^48),ch=getchar();
		r=w?-r:r;
	}
	template<typename T,typename ...Args>
	void read(T &x,Args &...args){read(x),read(args...);}
	#undef SIZE
}
using namespace IO;
const int Mod=998244353;
int Qpow(int a,int b){
	int Res=1;
	while(b){
		if(b&1)Res=1LL*Res*a%Mod;
		a=1LL*a*a%Mod;
		b>>=1;
	}
	return Res;
}
int n,K,Sum,f[N],inv[N],fac[N];
void Init(int n){
	fac[0]=fac[1]=1;
	for(int i=2;i<=n;i++)
		fac[i]=1LL*fac[i-1]*i%Mod;
	inv[n]=Qpow(fac[n],Mod-2);
	for(int i=n;i>=1;i--)
		inv[i-1]=1LL*inv[i]*i%Mod;
}
int main(){
	Init(N-10);
	read(n,K);
	f[0]=1,Sum=fac[n-1];
	for(int i=1;i<=n;i++){
		f[i]=1LL*Sum*inv[n-i]%Mod;
		if(i<n){
			(Sum+=1LL*f[i]*fac[n-i-1]%Mod)%=Mod;
			if(i>=K)Sum=(Sum-1LL*f[i-K]*fac[n-i+K-1]%Mod+Mod)%Mod;
		}
	}
	printf("%d\n",f[n]);
}