Option Explicit
'====================================================================================================
Sub Numerator()
Dim rng As Range
Dim x, arr, arrNum(1 To 1000000, 1 To 1) As Long
Dim r&, n&

On Error GoTo er
Set rng = Intersect(Selection, ActiveSheet.UsedRange)
If rng Is Nothing Then GoTo er
If rng.Areas.Count <> 1 Then GoTo er
If rng.Columns.Count <> 1 Then GoTo er

arr = rng.Value
If Not IsArray(arr) Then arr = Array(arr)

    For Each x In arr
        If IsError(x) Then GoTo nx
        If Len(x) = 0 Then GoTo nx
        If Not IsNumeric(x) Then GoTo nx
        x = --x: If x = 0 Or x <> Abs(CLng(x)) Then MsgBox "Find bad num!", vbCritical, "ERROR": Exit Sub

        For n = 1 To x
            r = r + 1
            If r > UBound(arrNum) Then MsgBox "Too many values!", vbCritical, "ERROR": Exit Sub
            arrNum(r, 1) = n
        Next n
nx: Next x

If r = 0 Then MsgBox "There is no values…", vbInformation, "NOTHING": Exit Sub

n = rng.Cells(1, 1).Column + 1
Columns(n).Insert
Cells(1, n).Resize(r, 1).Value = arrNum

Exit Sub
er: MsgBox "Something wrong!", vbCritical, "ERROR"
End Sub