#include using namespace std; using ll = long long; template struct prime_modint { using mint = prime_modint; unsigned int v; prime_modint() : v(0) {} prime_modint(unsigned int a) { a %= MOD; v = a; } prime_modint(unsigned long long a) { a %= MOD; v = a; } prime_modint(int a) { a %= (int)(MOD); if(a < 0)a += MOD; v = a; } prime_modint(long long a) { a %= (int)(MOD); if(a < 0)a += MOD; v = a; } static constexpr int mod() { return MOD; } mint& operator++() {v++; if(v == MOD)v = 0; return *this;} mint& operator--() {if(v == 0)v = MOD; v--; return *this;} mint operator++(int) { mint result = *this; ++*this; return result; } mint operator--(int) { mint result = *this; --*this; return result; } mint& operator+=(const mint& rhs) { v += rhs.v; if(v >= MOD) v -= MOD; return *this; } mint& operator-=(const mint& rhs) { if(v < rhs.v) v += MOD; v -= rhs.v; return *this; } mint& operator*=(const mint& rhs) { v = (unsigned int)((unsigned long long)(v) * rhs.v % MOD); return *this; } mint& operator/=(const mint& rhs) { return *this = *this * rhs.inv(); } mint operator+() const { return *this; } mint operator-() const { return mint() - *this; } mint pow(long long n) const { assert(0 <= n); mint r = 1, x = *this; while (n) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; } mint inv() const { assert(v); return pow(MOD - 2); } friend mint operator+(const mint& lhs, const mint& rhs) { return mint(lhs) += rhs; } friend mint operator-(const mint& lhs, const mint& rhs) { return mint(lhs) -= rhs; } friend mint operator*(const mint& lhs, const mint& rhs) { return mint(lhs) *= rhs; } friend mint operator/(const mint& lhs, const mint& rhs) { return mint(lhs) /= rhs; } friend bool operator==(const mint& lhs, const mint& rhs) { return (lhs.v == rhs.v); } friend bool operator!=(const mint& lhs, const mint& rhs) { return (lhs.v != rhs.v); } friend std::ostream& operator << (std::ostream &os, const mint& rhs) noexcept { return os << rhs.v; } }; //using mint = prime_modint<1000000007>; using mint = prime_modint<998244353>; int main(){ ios::sync_with_stdio(false); cin.tie(0); int n, p; cin >> n >> p; vector fact(n + 1), inv(n + 1); fact[0] = 1; for(int i = 1; i <= n; i++) fact[i] = i * fact[i - 1]; inv[n] = 1 / fact[n]; for(int i = n; i >= 1; i--) inv[i - 1] = i * inv[i]; auto comb = [&](int r, int c) -> mint { if(r < 0 || c < 0 || r < c) return 0; return fact[r] * inv[c] * inv[r - c]; }; mint ans = fact[n], coef = 1; for(int i = 0; i * p <= n; i++){ if(i) coef *= comb(n - (i - 1) * p, p) * fact[p - 1]; ans -= coef * inv[i]; } cout << ans << '\n'; }