mod=998244353
n,m=map(int,input().split())
dp=[[0 for i in range(46)] for j in range(m+1)]
dp2=[[0 for i in range(46)] for j in range(m+1)]
dp[0][0]=2
dp[0][1]=2
for i in range(n-1):
  for j in range(0,m+1):
    for k in range(0,45):
      dp2[j+k][k+1]+=dp[j][k]
      dp2[j+k][k]+=dp[j][k]*2
      dp2[j+k][abs(k-1)]+=dp[j][k]
      if j+k+1>m:
        break
  for j in range(0,m+1):
    for k in range(0,45):
      dp[j][k]=dp2[j][k]%mod
      dp2[j][k]=0
print(dp[m][0])