Build a series of number strings based on combinations of True and False in another column - excel

Question

Here's the table I'm working with:
I am manually inputting the "True" in column B for this project. For the example, I manually input column A, but the goal is to get the same results just from referencing column B.
I need it to count up, starting with 166 and add to the number string until it either hits a true, a double true (true back to back), or a double blank (blank cells back to back). For example, the first cell in column B is blank, the second cell is "True", and the third cell is blank - so it input 166, 167. If it went blank > True > True, the input would be 167, 168, 169 in the first three rows.
There can never be more than two trues in a row, only one or two. If there is two blanks in a row then only one number would be input (see 179).
I need to input the same contents (166, 167 for example) until either the blank>true>blank, blank>true>true, or blank>blank condition is met. Then it starts a new string and inputs based on the next condition, and so on.
Apologies for the row #'s being one off if that's confusing... the row numbers have no affect on the #'s in column A, need it to just reference column B.
Thank you for your time.

Answer 1

I think I got it to work. Please check out the code below. It should be installed in the code sheet of the worksheet on which you want the result.
Private Sub Worksheet_Change(ByVal Target As Range)
' Variatus #STO 07 Apr 2020
Dim Arr As Variant
Dim Rng As Range
Dim Result As String
Dim R As Long, Ra As Long
With Target
If .Cells.CountLarge > 1 Then Exit Sub
Set Rng = Range(Cells(2, 2), Cells(Rows.Count, 2).End(xlUp).Offset(1))
If Not Application.Intersect(Target, Rng) Is Nothing Then
Arr = Range(Cells(1, 1), Cells(Rows.Count, 2).End(xlUp).Offset(1)).Value
For R = 2 To Rng.Rows.Count
If Result = "" Then Result = ResultString(Result, R, Arr)
Arr(R, 1) = Result
Cells(R, 1).Value = Result
If R < UBound(Arr) Then
If Arr(R + 1, 2) = False Then
Result = ResultString(Result, R + 1, Arr)
End If
End If
Next R
End If
End With
End Sub
Private Function ResultString(ByVal Seed As Variant, _
ByVal R As Long, _
Arr As Variant) As String
' Variatus #STO 07 Apr 2020
Const Start As Integer = 166
Dim Fun As String
Dim Sp() As String
Dim i As Integer
On Error Resume Next
Sp = Split(Seed, ",")
Seed = Val(Sp(UBound(Sp))) + 1
If Err.Number Then Seed = Start
Fun = Seed
On Error GoTo 0
Do While (R + i) < UBound(Arr)
i = i + 1
If Arr(R + i, 2) = False Then Exit Do
Fun = Fun & ", " & CStr(Val(Seed) + i)
Loop
ResultString = Fun
End Function
The event procedure responds to changes in column B and will build column A according to the entries - True and False (or blank) - found there. The entire column must be rebuilt on each change. Observe the Const Start As Integer = 166 containing the start number.