from collections import *
from itertools import *
from functools import *
from heapq import *
import sys,math
input = sys.stdin.readline
# sys.setrecursionlimit(10**6)

N,K = map(int,input().split())

dp = [[0]*(K+1) for _ in range(K+1)]

dp[0][0] = 1
mod = 998244353
inv = pow(N,mod-2,mod)
for i in range(1,K+1):
    
    
    for j in range(i//2 + 1):
        
        dp[i][j] = (
            dp[i-1][j]*(N - i + 1 +2*j)*inv
            +dp[i-1][j-1]*(i + 1 - 2*j)*inv
                   )%mod


ans = 0
# print(dp)
for i in range(K//2 + 1):
    
    ans += dp[K][i]*(N+i)
    ans %= mod
print(ans)
# print(inv(3),2*inv(3)%mod)