No.3146 RE: Parentheses Counting
Story
It seems $N$ is large this time.
Problem Statement
Definition of a balanced parenthesis sequence
A string $X$ is a balanced parenthesis sequence if it satisfies the following.
- $X$ can be made into the empty string by repeating, $0$ or more times, the operation of deleting a
()contained in $X$ as a substring
For example, ()(()) and ()()()() are balanced parenthesis sequences, but ))(( and )()()( are not balanced parenthesis sequences.
For a balanced parenthesis sequence $T$, let $f(T)$ be the value of $x$ after performing the following procedure.
- Initially, let $S$ be the empty set and $x=0$, and do the following for $i=1, 2, \cdots, N$ in this order.
- If $T_i=$
(, add $i$ to $S$. - If $T_i=$
), let $j$ be the largest element contained in $S$, and add to $x$ the number of occurrences of()as a substring in the string obtained by extracting the open interval $(j, i)$ of $T$. Then, remove $j$ from $S$.
- If $T_i=$
For example, $f($()(())$)=1, f($(()()())$)=3$.
You are given a positive integer $N$. Find the sum of $f(S)$ over all possible strings that are balanced parenthesis sequences $S$ of length $N$.
Since the answer can be very large, find it modulo $998244353$.
You are given $T$ cases; answer each of them.
Notation for strings
For a string $A$, let $|A|$ be the length of $A$. Then $A_i(1\leq i\leq |A|)$ denotes the $i$-th character of $A$.Input
$T$ $case_1$ $case_2$ $\vdots$ $case_T$
$case_i$ represents the $i$-th case and is given in the following format.
$N$
- $1\leq T\leq 10^5$
- For each case, $1\leq N\leq 10^6$
Output
Output $T$ lines. On the $k(1\leq k\leq T)$-th line, output the answer for the $k$-th case.
For each case, let $r$ be the sum of $f(S)$ modulo $998244353$, and output it in the following format.
$r$
Print a newline at the end.
Sample
Sample 1
Input
3 4 2 11
Output
1 0 0
For example, in the 1st case, the balanced parenthesis sequences of length $4$ are the 2 strings ()() and (()). Since $f($()()$)=0, f($(())$)=1$, output 1.
In the 3rd case, no balanced parenthesis sequence of length $11$ exists. Therefore, output 0.
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