Error in macro that automatically inserts numbers

Hi guys,

Please help me with the following code for automatically updating numbers when rows are inserted/deleted. VBA gives me an error on the line:

Range("A & LastCell + 1:A" & Rows.Count) = ""

The code is below...

Private Sub Worksheet_Change(ByVal Target As Range)
    
Dim StartNum As Long
Dim FirstCell As Long
Dim LastCell As Long

StartNum = 1
FirstCell = 8
LastCell = 357

Application.EnableEvents = False
    Do While FirstCell <= LastCell
    Range("A" & FirstCell).Value = StartNum
    FirstCell = FirstCell + 1
    StartNum = StartNum + 1
    Loop
    Range("A & LastCell + 1:A" & Rows.Count) = ""
Application.EnableEvents = True

End Sub

Why is my synatx wrong. Should I put a .Value after the last bracket? Please take my hand and point me in the right direction.

Thanks
B