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## 题目描述

Sagume finds that there is too much filth in Gensoukyou that she can't endure any more. She decides to clean up the Gensoukyou. There are N places in Gensoukyou which form a straight line, numbered from 1 to N. Places with the adjacent number can reach each other. To clean up all places, Sagume will follow the following procedure:

1. She randomly choose a place within the current connected component and clean it out. It will take her S seconds, in which S represents the current connected component's size.
2. She cut off the chosen place, then there will appear at most 2 new connected components.
3. She subsequently go to clean up the new components.

As a grand sage, Sagume is tight for time. She wants to know the expected time she will cost in order to schedule her time.

## 输入

The first line contains an integer T, the number of test cases.
Each test case contains an integer N, the number of places in Gensoukyou.
It is guaranteed that 1<=T<=1e4 and 1<=N<=1e6.

## 输出

For each test case, output one real number within a single line, which is the expected time(seconds) Sagume will cost. Your answer will be considered correct if its absolute error does not exceed 1e-4.

```2
3
4```

## 样例输出

```5.6667
8.8333```

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