#include <bits/stdc++.h>
#define mod 998244353
#define File(xxx) freopen(xxx".in","r",stdin),freopen(xxx".out","w",stdout)
using namespace std;
typedef long long LL;
const int N = 1e7+5;
int n, k, jc[N], inv[N], a[N], sum[N];

template <typename T> inline void debug(T x) { cerr<<x; }
template <typename T, typename ...T_> inline void debug(T x, T_ ...p) { cerr<<x<<' ', debug(p...); }
template <typename T> void read(T& x) {
	x = 0; int f = 0; char c = getchar();
	while(c < '0' || c > '9') f |= (c == '-'), c=getchar();
	while(c >= '0' && c <= '9') x=(x<<1)+(x<<3)+(c^48), c=getchar();
	x=(f ? -x : x);
}
int lne; char put[105];
template <typename T> void write(T x, char ch) {
	lne = 0; if(x < 0) putchar('-'), x=-x;
	do { put[++lne]=x%10, x/=10; } while(x);
	while(lne) putchar(put[lne--]^48);
	putchar(ch);
}
int upd(int x) {
	return (x >= mod ? x-mod : x);
}

signed main() {
	read(n), read(k);
	jc[0]=jc[1]=inv[0]=inv[1]=1;
	for(int i = 2; i <= n; ++i)
		jc[i]=1LL*jc[i-1]*i%mod, inv[i]=1LL*(mod-mod/i)*inv[mod%i]%mod;
	a[0]=1;
	sum[0]=1;
	for(int i = 1; i <= n; ++i) {
		a[i]=1LL*upd(sum[i-1]-(i > k ? sum[i-k-1] : 0)+mod)*inv[n-i]%mod;
		sum[i]=upd(sum[i-1]+a[i]);
	}
	write(1LL*a[n]*jc[n-1]%mod, '\n');
	return 0;
}