Range("g1:h1").Copy Range("g2:h2").Resize(1 * n)

Sub Размножить()
    Dim lngCalc As Long
    Dim n&
    n = Val(InputBox("n ="))
     
    Application.ScreenUpdating = False
    lngCalc = Application.Calculation
    Application.Calculation = xlCalculationManual
    Application.DisplayAlerts = False
     
    Range("g1:h1").Copy Range("g2:h2").Resize(1 * n)
     
    Application.ScreenUpdating = True
    Application.Calculation = lngCalc
    Application.DisplayAlerts = True
    MsgBox "Готово!", vbInformation
End Sub

Sub random()
[a1:o1000000].Clear
    n = Val(InputBox("Верхний предел выборки"))
    m = Val(InputBox("Количество генерируемых чисел"))
    Dim i As Long, j As Long, a() As Long, b As Long
    ReDim a(1 To n) As Long
    Randomize
    For b = 1 To 1000000
    For i = 1 To n
              j = Int(Rnd() * i + 1)
        If j <> i Then a(i) = a(j)
        a(j) = i
    Next i
        Cells(b, 1).Resize(, m) = a
    Next b
End Sub