Sub Макрос2()
    For i =  1  To  100 
          If Not Left(Cells(x, i).Formula,  1 ) = "=" Then
              For n ...
                ...
              Next n
          End If
    Next i
End Sub

Sub Макрос1()
Dim RngWithFormulae As Range

    Set RngWithFormulae = Cells.SpecialCells(xlCellTypeFormulas _
        , xlErrors + xlLogical + xlNumbers + xlTextValues)
    
    For i =  1  To  100 
          If Intersect(Cells(x, i), RngWithFormulae) Is Nothing Then
              For n ...
                ...
              Next n
          End If
    Next i
    
    Set RngWithFormulae = Nothing
End Sub

foreach c in range("A1:A100")
    if c.HasFormula() then
        .....
    end if
next