CF1777B.Emordnilap

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题目描述

A permutation of length nn is an array consisting of nn distinct integers from 11 to nn in arbitrary order. For example, [2,3,1,5,4][2,3,1,5,4] is a permutation, but [1,2,2][1,2,2] is not a permutation ( 22 appears twice in the array), and [1,3,4][1,3,4] is also not a permutation ( n=3n=3 but there is 44 in the array). There are n!=n(n1)(n2)1n! = n \cdot (n-1) \cdot (n - 2) \cdot \ldots \cdot 1 different permutations of length nn .

Given a permutation pp of nn numbers, we create an array aa consisting of 2n2n numbers, which is equal to pp concatenated with its reverse. We then define the beauty of pp as the number of inversions in aa .

The number of inversions in the array aa is the number of pairs of indices ii , jj such that i<ji < j and ai>aja_i > a_j .

For example, for permutation p=[1,2]p = [1, 2] , aa would be [1,2,2,1][1, 2, 2, 1] . The inversions in aa are (2,4)(2, 4) and (3,4)(3, 4) (assuming 1-based indexing). Hence, the beauty of pp is 22 .

Your task is to find the sum of beauties of all n!n! permutations of size nn . Print the remainder we get when dividing this value by 10000000071\,000\,000\,007 ( 109+710^9 + 7 ).

输入格式

Each test contains multiple test cases. The first line contains the number of test cases tt ( 1t1051 \le t \le 10^5 ). The description of the test cases follows.

Each test case has only one line — the integer nn ( 1n1051 \leq n \leq 10^5 ).

It is guaranteed that the sum of nn over all test cases does not exceed 10510^5 .

输出格式

For each test case, print one integer — the sum of beauties of all permutations of size nn modulo 10000000071\,000\,000\,007 ( 109+710^9 + 7 ).

输入输出样例

  • 输入#1

    3
    1
    2
    100

    输出#1

    0
    4
    389456655

说明/提示

For the first test case of the example, p=[1]p = [1] is the only permutation. a=[1,1]a = [1, 1] has 00 inversions.

For the second test case of the example, the permutations are [1,2][1, 2] and [2,1][2, 1] . Their respective aa arrays are [1,2,2,1][1, 2, 2, 1] and [2,1,1,2][2, 1, 1, 2] , both of which have 22 inversions.

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