PP1 and Competitive Programming
Reduce to one
Consider a list of integers L. Initially L contains the integers 1 through n, each of them exactly once (but it may contain multiple copies of some integers later). The order of elements in L is not important. You should perform the following operation n − 1 times:
- Choose two elements of the list, let's denote them by x and y. These two elements may be equal.
- Erase the chosen elements from L.
- Append the number x + y + x * y to L.
At the end, L contains exactly one integer. Find the maximum possible value of this integer. Since the answer may be large, compute it modulo
109 + 7.
The first line contains the number of test cases t. Each of the next t lines contains a single integer n (1 ≤ n ≤
For each test case, print a single line containing one integer - the maximum possible value of the final number in the list modulo
109 + 7.
3 1 2 4
1 5 119