from math import sqrt
from copy import deepcopy

mod = 998244353
N, M = map(int, input().split())
sq = int(sqrt(2 * M) + 3)

init = [[0] * (M + 1) for _ in range(sq)]
dp = deepcopy(init)
dp[0][0] = 1

for _ in range(N):
  nx = deepcopy(init)
  for i in range(sq):
    for j in range(M + 1):
      if dp[i][j] == 0:
        continue
      im1 = abs(i - 1)
      if j + im1 <= M:
        nx[im1][j + im1] += dp[i][j]
        nx[im1][j + im1] %= mod
      if j + i <= M:
        nx[i][j + i] += dp[i][j] * 2
        nx[i][j + i] %= mod
      if i != sq - 1 and j + i + 1 <= M:
        nx[i + 1][j + i + 1] += dp[i][j]
        nx[i + 1][j + i + 1] %= mod
  dp = nx

print(dp[0][M])