Codeforces Round 745 (Div. 2)
A
CQXYM Count Permutations
Codeforces
800
原题
←B →
翻译中…

CQXYM is counting permutations length of $2n$.

翻译中…

A permutation is an array consisting of $n$ distinct integers from $1$ to $n$ in arbitrary order. For example, $[2,3,1,5,4]$ is a permutation, but $[1,2,2]$ is not a permutation ($2$ appears twice in the array) and $[1,3,4]$ is also not a permutation ($n=3$ but there is $4$ in the array).

翻译中…

A permutation $p$(length of $2n$) will be counted only if the number of $i$ satisfying $p_i \lt p_{i+1}$ is no less than $n$. For example:

翻译中…
  • Permutation $[1, 2, 3, 4]$ will count, because the number of such $i$ that $p_i \lt p_{i+1}$ equals $3$ ($i = 1$, $i = 2$, $i = 3$).
  • Permutation $[3, 2, 1, 4]$ won't count, because the number of such $i$ that $p_i \lt p_{i+1}$ equals $1$ ($i = 3$).
翻译中…

CQXYM wants you to help him to count the number of such permutations modulo $1000000007$ ($10^9+7$).

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In addition, modulo operation is to get the remainder. For example:

翻译中…
  • $7 \mod 3=1$, because $7 = 3 \cdot 2 + 1$,
  • $15 \mod 4=3$, because $15 = 4 \cdot 3 + 3$.
翻译中…

Input

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The input consists of multiple test cases.

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The first line contains an integer $t (t \geq 1)$ — the number of test cases. The description of the test cases follows.

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Only one line of each test case contains an integer $n(1 \leq n \leq 10^5)$.

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It is guaranteed that the sum of $n$ over all test cases does not exceed $10^5$

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Output

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For each test case, print the answer in a single line.

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Note

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$n=1$, there is only one permutation that satisfies the condition: $[1,2].$

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In permutation $[1,2]$, $p_1 \lt p_2$, and there is one $i=1$ satisfy the condition. Since $1 \geq n$, this permutation should be counted. In permutation $[2,1]$, $p_1 \gt p_2$. Because $0 \lt n$, this permutation should not be counted.

翻译中…

$n=2$, there are $12$ permutations: $[1,2,3,4],[1,2,4,3],[1,3,2,4],[1,3,4,2],[1,4,2,3],[2,1,3,4],[2,3,1,4],[2,3,4,1],[2,4,1,3],[3,1,2,4],[3,4,1,2],[4,1,2,3].$

翻译中…

样例

Input #1
4
1
2
9
91234
Output #1
1
12
830455698
890287984
InputCopy OutputCopy
题目信息
题号
1581A
时间限制
1 s
内存限制
256 MB
标签
组合数学
数学
数论

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。