def extgcd(a, b):
    if b:
        d, y, x = extgcd(b, a % b)
        y -= (a // b) * x
        return d, x, y
    return a, 1, 0

#以下modinv
def mod_inv(a, m):
    g, x, y = extgcd(a, m)

    if g != 1:
        raise Exception()

    if x < 0:
        x += m

    return x

N,K=map(int,input().split())
dp=[[0 for _ in range(K+1)] for _ in range(K+1)]
#dp[イエローカード提示数][人が抜けた数]
dp[0][0]=1
p=998244353
inv=mod_inv(N,p)
for i in range(K):
    for j in range(i//2+1):
        dp[i+1][j]+=dp[i][j]*inv*(N-(i-j*2))%p
        dp[i+1][j]%=p
        dp[i+1][j+1]+=dp[i][j]*inv*(i-j*2)%p
        dp[i+1][j+1]%=p
ans=0
for j in range(K+1):
    ans+=(N+j)*dp[-1][j]
    ans%=p
print(ans)