MOD = 998244353

n,k = map(int, input().split())

dp = [0 for i in range(6)]
dp[0] = 1

div = pow(6, MOD-2, MOD)

for i in range(n):
    ndp = [0 for i in range(6)]
    for j in range(6):
        dist = dp[j] * div % MOD
        for k in range(6):

            ndp[k] += dist
    dp = ndp

print(dp[k])