1718. Construct the Lexicographically Largest Valid Sequence

Given an integer n, find a sequence with elements in the range [1, n] that satisfies all of the following: - The integer 1 occurs once in the sequence. - Each integer between 2 and n occurs twice in the sequence. - For every integer i between 2 and n, the distance between the two occurrences of i is exactly i. The distance between two numbers on the sequence, a[i] and a[j], is the absolute dif