N,K=map(int, input().split())
dp1 = [0]*(K+1)
dp1[0] = 1
for i in range(1, 2*N+1):
    dp1_d = [0]*(K+1)
    for j in range(K+1):
        if j!=0:
            dp1_d[j] += dp1[j-1]
            dp1_d[j] %= 998244353
        if j != K:
            dp1_d[j] += dp1[j+1]
            dp1_d[j] %= 998244353
    dp1 = dp1_d
tmp = dp1[0]
dp1 = [0]*K
dp1[0] = 1
for i in range(1, 2*N+1):
    dp1_d = [0]*(K)
    for j in range(K):
        if j!=0:
            dp1_d[j] += dp1[j-1]
            dp1_d[j] %= 998244353
        if j != K-1:
            dp1_d[j] += dp1[j+1]
            dp1_d[j] %= 998244353
    dp1 = dp1_d
print((tmp - dp1[0])% 998244353)