mod = 998244353

n, m = map(int, input().split())

K = 31
dp = [[0] * (m + 1) for i in range(K + 1)]
dp[0][0] = 1

for _ in range(n):
    ndp = [[0] * (m + 1) for i in range(K + 1)]
    for d in range(K + 1):
        for s in range(m + 1):
            if d == 0:
                res = [(1, 2), (0, 2)]
            else:
                res = [(d - 1, 1), (d, 2), (d + 1, 1)]
            for nd, w in res:
                ns = s + nd
                if ns <= m and nd <= K:
                    ndp[nd][ns] += dp[d][s] * w
                    ndp[nd][ns] %= mod

    dp = ndp

print(dp[0][m])