N, K = map(int, input().split())
mod = 998244353
inv = pow(N, mod - 2, mod)
pre = [0] * (N + 5)
pre[0] = 1
for _ in range(K):
    dp = [0] * (N + 5)
    for i in range(N + 1):
        dp[i + 1] += pre[i] * (N - i) * inv
        dp[i - 1] += pre[i] * i * inv
        dp[i + 1] %= mod
        dp[i - 1] %= mod
    dp, pre = pre, dp
    
ans = N
inv = pow(2, mod - 2, mod)
for i in range(N + 1):
    ans += (K - i) * pre[i] * inv
    ans %= mod
    
print(ans)