import java.util.Scanner;

public class Main {
	public static void main(String[] args) throws Exception {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int k = sc.nextInt();
		sc.close();

		int n2 = n * 2;
		int mod = 998244353;
		int[][] dp0 = new int[n2 + 1][k + 1];
		int[][] dp1 = new int[n2 + 1][k + 1];
		dp0[0][0] = 1;
		for (int i = 0; i < n2; i++) {
			for (int j = 0; j < k; j++) {
				dp0[i + 1][j + 1] += dp0[i][j];
				dp1[i + 1][j + 1] += dp1[i][j];
				dp0[i + 1][j + 1] %= mod;
				dp1[i + 1][j + 1] %= mod;
			}
			dp1[i + 1][k] += dp0[i + 1][k];
			dp1[i + 1][k] %= mod;
			dp0[i + 1][k] = 0;
			for (int j = 1; j <= k; j++) {
				dp0[i + 1][j - 1] += dp0[i][j];
				dp1[i + 1][j - 1] += dp1[i][j];
				dp0[i + 1][j - 1] %= mod;
				dp1[i + 1][j - 1] %= mod;
			}
		}
		System.out.println(dp1[n2][0]);
	}
}