#include <bits/stdc++.h>
#define int long long
using namespace std;
void file(string x)
{
    freopen((x + ".in").c_str(), "r", stdin);
    freopen((x + ".out").c_str(), "w", stdout);
}
const int maxn = 1e7 + 5, mod = 998244353;
int dp[maxn], n, k, fac[maxn], inv[maxn];
void add(int &x, int y) { (x += y) >= mod && (x -= mod); }
int ksm(int x, int y)
{
    int ans = 1;
    while (y)
    {
        if (y & 1) ans = ans * x % mod;
        x = x * x % mod, y >>= 1;
    }
    return ans;
}
int A(int x, int y)
{
    return fac[x] * inv[x - y] % mod;
}
signed main()
{
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    cin >> n >> k;
    fac[0] = inv[0] = 1;
    for (int i = 1; i <= n; i++) fac[i] = fac[i - 1] * i % mod;
    inv[n] = ksm(fac[n], mod - 2);
    for (int i = n - 1; i >= 1; i--) inv[i] = inv[i + 1] * (i + 1) % mod;
    dp[0] = 1;
    int sum = fac[n - 1];
    for (int i = 1; i <= n; i++)
    {
        if (i > k)
            add(sum, mod - dp[i - k - 1] * fac[n - i + k] % mod);
        dp[i] = sum * inv[n - i] % mod;
        if (i != n)
            add(sum, dp[i] * fac[n - i - 1] % mod);
    }
    cout << dp[n];
    return 0;
}