#include <bits/stdc++.h>
using namespace std;
namespace basic{
#define int long long
#define uint unsigned int
#define per(i,a,b) for(int i=(a);i<=(b);i++)
#define perr(i,a,b,c) for(int i=(a);i<=(b);i+=(c))
#define rep(i,b,a) for(int i=(b);i>=(a);i--)
#define epb emplace_back
#define bit(x) (1ll<<(x))
#define all(x,l,r) &(x)[l],&(x)[r]+1
#define vall(x) (x).begin(),(x).end()
#define lowbit(x) ((x)&(-(x)))
#define pc(x) putchar(x)
#define turn(x) (x-'a'+1)
#define cto const auto
template <class T> bool chkmn(T &x,T y){return x>y?(x=y,1):0;}
template <class T> bool chkmn(T &x,T y,T z){return y<z?(x=y,1):(x=z,0);}
template <class T> bool chkmx(T &x,T y){return x<y?(x=y,1):0;}
template <class T> bool chkmx(T &x,T y,T z){return y>z?(x=y,1):(x=z,0);}
char *p1,*p2,buf[100000];
#define nc() (p1==p2 && (p2=(p1=buf)+fread(buf,1,100000,stdin),p1==p2)?EOF:*p1++)
int read(){
    int x=0,f=1;char ch=nc();
    while(ch<48||ch>57){if(ch=='-') f=-1;ch=nc();}
    while(ch>=48&&ch<=57) x=x*10+ch-48,ch=nc();
    return x*f;
}
void write(int x){
    if(x<0) pc('-'),x=-x;
    if(x>9) write(x/10);
    pc(x%10+'0');
}
void print(string s,char op=0){for(auto x:s) pc(x);op&&pc(op);}
void print(int x,char op=0){write(x);op&&pc(op);}
}
using namespace basic;
namespace fisher{
bool mbe;void cntime();
const int N=1e7+5,mod=998244353;
int n,k,f[N];
int fac[N],inv[N];
int gmod(int x){
    return x<-mod?x%mod+mod:(x<0?x+mod:(x<mod?x:(x<(mod<<1)?x-mod:x%mod)));
}
int qpow(int a,int b){
    int res=1;
    for(;b;b>>=1,a=gmod(a*a))
        if(b&1) res=gmod(res*a);
    return res;
}
int A(int n,int m){
    if(n<m) return 0;
    return gmod(fac[n]*inv[n-m]);
}
void main(){
    n=read();k=read();
    fac[0]=inv[0]=1;
    per(i,1,n) fac[i]=gmod(fac[i-1]*i);
    inv[n]=qpow(fac[n],mod-2);
    rep(i,n-1,1) inv[i]=gmod(inv[i+1]*(i+1));
    per(i,0,k) f[i]=fac[i];
    per(i,k+1,n)
        f[i]=gmod(gmod(f[i-1]*i)-gmod(A(i-2,k-1)*gmod(f[i-k-1]*(i-1))));
    print(f[n],'\n');
    return cntime();
}
bool mbd;void cntime(){
    cerr<<"Memory: "<<abs(&mbd-&mbe)/1048476.0<<" MB\n";
    cerr<<"Time: "<<1e3*clock()/CLOCKS_PER_SEC<<" ms\n";
}}
signed main(){
    fisher::main();
    return 0;
}