1721.
Rikka with Rock-paper-scissors
时间限制 8000 ms
内存限制 64 MB
As we know, Rikka is poor at math. Yuta is worrying about this situation, so he gives Rikka some math tasks to practice. There is one of them:
Alice and Bob are going to play a famous game: Rock-paper-scissors. Both of them don't like to think a lot, so both of them will use the random strategy: choose rock/paper/scissors in equal probability.
They want to play this game $n$ times, then they will calculate the score $s$ in the following way: if Alice wins $a$ times, Bob wins $b$ times, and in the remaining $n-a-b$ games they make a tie, the score will be the greatest common divisor of $a$ and $b$.
Know Yuta wants to know the expected value of $s \times 3^{2n}$. It is easy to find that the answer must be an integer.
It is too difficult for Rikka. Can you help her?
Note: If one of $a,b$ is $0$, we define the greatest common divisor of $a$ and $b$ as $a+b$.
输入数据
输出数据
For each testcase, print a single line with a single number -- the answer modulo $mo$.
样例输入
复制
5
1 998244353
2 998244353
3 998244353
4 998244353
5 998244353
\n
· \n
· \n
· \n
· \n
· \n
样例输出
复制
6
90
972
9720
89910
\n
\n
\n
\n
\n