AT_fps_24_a お菓子

Description

For $ D $ days, each day you choose exactly one of the following four actions: - Pay $ 1 $ yen and buy gum. - Pay $ 3 $ yen and buy candy. - Pay $ 4 $ yen and buy chocolate. - Pay $ 6 $ yen and buy wheat gluten snack. After $ D $ days, you have paid a total of $ N $ yen. How many possible sequences of $ D $ days satisfy this condition? Output the answer modulo $ 998244353 $ . Two sequences are considered different if there exists at least one day on which the purchased item is different.

Input Format

The input is given from standard input in the following format: > $ D $ $ N $

Output Format

Print the answer.

Explanation/Hint

### Sample Explanation 1 There are $ 4 $ valid action sequences for $ 2 $ days: - On day $ 1 $ , pay $ 1 $ yen for gum; on day $ 2 $ , pay $ 6 $ yen for wheat gluten snack. - On day $ 1 $ , pay $ 3 $ yen for candy; on day $ 2 $ , pay $ 4 $ yen for chocolate. - On day $ 1 $ , pay $ 4 $ yen for chocolate; on day $ 2 $ , pay $ 3 $ yen for candy. - On day $ 1 $ , pay $ 6 $ yen for wheat gluten snack; on day $ 2 $ , pay $ 1 $ yen for gum. ### Constraints - $ 1 \leq D \leq 2 \times 10^5 $ - $ 1 \leq N \leq 10^6 $ - $ D, N $ are integers