MOD = 998244353
N, K = map(int, input().split())

inv6 = pow(6, MOD-2, MOD)

dp = [[0] * 6 for _ in range(N+1)]
dp[0][0] = 1
for i in range(N):
    for j in range(6):
        for k in range(1, 7):
            m = (j + k) % 6
            dp[i+1][m] += dp[i][j] * inv6
            dp[i+1][m] %= MOD

ans = dp[N][K]
print(ans)