☆ENGLISH ONLY☆コミュのHow about some math?

Alright, as you're reading this, you're obviously bored.
Then, how about giving it a shot on some math? I'm sure you can kill your time to a certain extent.

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Any natural number becomes 1 using the following rules.

Rule 1: If the number is odd, add 1.
Rule 2: If the number is even, divide by 2.

Example: 7 - 8 - 4 - 2 - 1

With following the rules, 7 becomes 1 by 4 times.

1. How many times does it take 17 to become 1 ?

2. Find all numbers which become 1 by 5 times.

3. Some number becomes 1 by 8 times. Rule1 is used only once and Rule2 is used for the rest. However, by mistake, 1 was deducted from the number instead of being added on it. As a result, the number has become 1 by 7 times. Find out this number.

Enjoy :D