Collatz conjecture

Hello everyone!

The Collatz conjecture is a conjecture in mathematics that concerns a sequence defined as follows: start with any positive integer n. Then each term is obtained from the previous term as follows: if the previous term is even, the next term is one half the previous term. Otherwise, the next term is 3 times the previous term plus 1. The conjecture is that no matter what value of n, the sequence will always reach 1.

I am trying to program something that will show me the amount of steps (of loops) that happened before the number n became smaller than the initial number.
It is the variable dva, but I don't know how to find it!
then I also need to show every step: every value of n (one or each loop) and
Also the highest value that n takes throughout the loops (am)
and the number of steps until n reaches 1 (dv)

I have started something but I feel stuck moving forward as the beginning doesn't even work..

can someone point me to where I'm messing up here?

Sub collatz2()
n = InputBox("type in a number ")

am = 0

Do While n <> 1
    If n Mod 2 = 0 Then
        n = n * 2
    Else: n = n * 3 = 1
    End If

If n > am Then
    Z = am
End If

x = x + 1
Dim ligne As Integer
'Cells(1, 1).Value = "Trip"
Cells(x, 1).Value = n

Loop

'Cells(1, 2).Value = "Steps"
Cells(x, 2).Value = x

'Cells(1, 3).Value = "Maximal altitude"
Cells(x, 3).Value = am

End Sub