mod = 998244353
n, k = map(int,input().split())
ans = n
ninv = pow(n, mod-2, mod)

dp = [[0] * (n+1) for i in range(k+1)]
dp[0][0] = 1
for i in range(k):
	for j in range(n+1):
		if j > 0:
			dp[i+1][j-1] += j * ninv % mod * dp[i][j]
			dp[i+1][j-1] %= mod
			ans += j * ninv % mod * dp[i][j] % mod
		if j < n:
			dp[i+1][j+1] += (n-j) * ninv % mod * dp[i][j]
			dp[i+1][j+1] %= mod

ans %= mod
print(ans)