/*
*/

#include <bits/stdc++.h>
using namespace std;
#define ALL(x) (x).begin(), (x).end()
#define REP(i, n) for(ll i=0; i<(ll)(n); i++)
#define RREP(i, n) for(ll i=(ll)(n)-1; i>=0; i--)

template<typename T> int LB(const vector<T>& v, T x) { return lower_bound(ALL(v),x)-v.begin(); }
template<typename T> int UQ(T& v) { sort(ALL(v)); v.erase(unique(ALL(v)),v.end()); return v.size(); }
template<typename T> bool chmax(T& a, T b) { return a<b ? a=b, true : false; }
template<typename T> bool chmin(T& a, T b) { return a>b ? a=b, true : false; }
template<typename T> using rpriority_queue=priority_queue<T,vector<T>,greater<T>>;
using ll=long long; const int INF=1e9+10; const ll INFL=4e18;
using ld=long double; using lll=__int128_t; using ull=unsigned long long;
using VI=vector<int>; using VVI=vector<VI>; using VL=vector<ll>; using VVL=vector<VL>;
using PL=pair<ll,ll>; using VP=vector<PL>; using WG=vector<vector<pair<int,ll>>>;


#ifdef LOCAL
#include "./debug.hpp"
#else
#define debug(...)
#define print_line
#endif



/// @brief ModInt
template<ll MOD>
struct ModInt {
    ModInt(ll x=0){ value=(x>=0?x%MOD:MOD-(-x)%MOD); }

    ModInt operator-() const { return ModInt(-value); }
    ModInt operator+() const { return ModInt(*this); }
    ModInt& operator+=(const ModInt& other) {
        value+=other.value;
        if(value>=MOD) value-=MOD;
        return*this;
    }
    ModInt& operator-=(const ModInt& other) {
        value+=MOD-other.value;
        if(value>=MOD) value-=MOD;
        return*this;
    }
    ModInt& operator*=(const ModInt other) {
        value=value*other.value%MOD;
        return*this;
    }
    ModInt& operator/=(ModInt other) {
        (*this)*=other.inv();
        return*this;
    }
    ModInt operator+(const ModInt& other) const { return ModInt(*this)+=other; }
    ModInt operator-(const ModInt& other) const { return ModInt(*this)-=other; }
    ModInt operator*(const ModInt& other) const { return ModInt(*this)*=other; }
    ModInt operator/(const ModInt& other) const { return ModInt(*this)/=other; }
    bool operator==(const ModInt& other) const { return value==other.value; }
    bool operator!=(const ModInt& other) const { return value!=other.value; }
    friend ostream& operator<<(ostream& os, const ModInt& x) { return os<<x.value; }
    friend istream& operator>>(istream& is, ModInt& x) {
        ll v;
        is>>v;
        x=ModInt<MOD>(v);
        return is;
    }

    ModInt pow(ll x) const { 
        ModInt ret(1),mul(value);
        while(x) {
            if(x&1) ret*=mul;
            mul*=mul;
            x>>=1;
        }
        return ret;
    }
    ModInt inv() const { return pow(MOD-2); }
    ll val() {return value; }
    static constexpr ll mod() { return MOD; }

private:
    ll value;
};

using Mod998=ModInt<998244353>;
using Mod107=ModInt<1000000007>;

#define VM vector<mint>
#define VVM vector<vector<mint>>


/// @brief 二項係数・階乗計算
template<typename T>
struct Combinatorics {
    Combinatorics()=default;

    /// @brief 二項係数の前計算
    /// @note O(N)
    Combinatorics(int n) {
        fac=vector<T>(n+1);
        finv=vector<T>(n+1);
        fac[0]=1;
        for(int i=1; i<=n; i++) fac[i]=fac[i-1]*i;
        finv[n]=fac[n].inv();
        for(int i=n; i>=1; i--) finv[i-1]=finv[i]*i;
    }

    /// @brief nCr を返す
    /// @note n < 0, r < 0, n < r のときは 0 を返す
    T comb(ll n, ll r) {
        if(n<0 || r<0 || n-r<0) return 0;
        return fac[n]*finv[r]*finv[n-r];
    }

    /// @brief nPr を返す
    /// @note n < 0, r < 0, n < r のときは 0 を返す
    T perm(ll n, ll r) {
        if(n<0 || r<0 || n-r<0) return 0;
        return fac[n]*finv[n-r];
    }

    /// @brief n! を返す
    T factrial(int n) { return fac[n]; }

    /// @brief (n!)^-1 を返す
    T factinv(int n) { return finv[n]; }

    /// @brief nCr を返す
    T operator()(ll n, ll r) { return comb(n,r); }

    T cataran(ll n) { return fac[2*n]*finv[n+1]*finv[n]; }

private:
    vector<T> fac,finv;
};

using mint=Mod998;
//----------------------------------------------------------

void solve() {
    ll N,K; cin>>N>>K;
    Combinatorics<mint> comb(1e6);

    VVM dp0(N+1,VM(N+1)), dp1=dp0;
    dp0[0][0]=1;
    REP(i,N) {
        for(ll j=i; j<=N && j<=i+K; j++) {
            if(j>i && i+1<=N) {
                dp0[i+1][j]+=dp0[i][j];
                dp1[i+1][j]+=dp1[i][j];
            }
            if(j+1<=N && j+1<i+K) {
                dp0[i][j+1]+=dp0[i][j];
                dp1[i][j+1]+=dp1[i][j];
            }
            else if(j+1<=N && j+1==i+K) {
                dp1[i][j+1]+=dp0[i][j]+dp1[i][j];
            }
        }
    }
    debug(dp0);
    debug(dp1);

    cout<<dp1[N][N]<<endl;
}

int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);
    //cout<<fixed<<setprecision(15);
    int T=1;
    //cin>>T;
    while(T--) solve();
}