#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ull = unsigned long long;
using db = double;

#define For(i, j, k) for (int i = (j); i <= (k); i++)
#define ForDown(i, j, k) for (int i = (j); i >= (k); i--)

namespace {
ll qpow(ll x, ull y, ll mod) {
  ll ans = 1;
  while (y) {
    if (y & 1)
      (ans *= x) %= mod;
    (x *= x) %= mod, y >>= 1;
  }
  return ans;
}
constexpr ll MAXN = 1e7 + 5, mod = 998244353;
int n, k;
ll fac[MAXN], ifac[MAXN], f[MAXN], g[MAXN];
ll A(int x, int y) {
  if (x < 0 || y < 0 || x < y)
    return 0;
  return fac[x] * ifac[x - y] % mod;
}
void Main() {
  cin.tie(0)->sync_with_stdio(0);
  cin >> n >> k;
  fac[0] = 1;
  For(i, 1, n) fac[i] = fac[i - 1] * i % mod;
  ifac[n] = qpow(fac[n], mod - 2, mod);
  ForDown(i, n, 1) ifac[i - 1] = ifac[i] * i % mod;
  f[0] = 1, g[0] = fac[n - 1];
  For(i, 1, n) {
    f[i] = (mod + g[i - 1] - (i - k > 0 ? g[i - k - 1] : 0)) * ifac[n - i] % mod;
    if (i < n)
      g[i] = (g[i - 1] + f[i] * fac[n - i - 1]) % mod;
  }
  cout << f[n] << '\n';
}
}

int main() { return Main(), 0; }