n,k = map(int,input().split())
mod = 998244353; d = pow(n,-1,mod); dp = [1]+[0]*n; e = 0
for _ in range(k):
    eq = [0]*(n+1)
    for i in range(n+1):
        if i>0: eq[i-1] = (eq[i-1]+dp[i]*i*d)%mod
        if i<n: eq[i+1] = (eq[i+1]+dp[i]*(n-i)*d)%mod
    dp = eq
for i,v in enumerate(dp): e += ((k-i)//2+n)*v
print(e%mod)