from math import sqrt

mod = 998244353
N, M = map(int, input().split())

dp = [[0] * (M + 1) for _ in range(50)]
nx = [[0] * (M + 1) for _ in range(50)]
dp[0][0] = 1

for _ in range(N):
  for i in range(50):
    for j in range(M + 1):
      nx[i][j] = 0
  for i in range(50):
    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]
      if j + i <= M:
        nx[i][j + i] += dp[i][j] * 2
      if i != 50 - 1 and j + i + 1 <= M:
        nx[i + 1][j + i + 1] += dp[i][j]
  dp, nx = nx, dp
  for i in range(50):
    for j in range(M + 1):
      dp[i][j] %= mod

print(dp[0][M])