http://rosettacode.org/wiki/Ackermann_function

Uses "Console"

Dim i,j As Long

For i = 0 To 3
  For j = 0 To 7
    PrintL ("Ackermann " & i & " " & j & " " & ackermann(i,j))
  Next
Next


Function ackermann(m As Long, n As Long)

If m = 0 Then
  Function  = n + 1
ElseIf n = 0 Then
  Function = ackermann(m-1,1)   
Else
  Function = ackermann(m-1,ackermann(m,n-1))
End If
  
End Function

PrintL "Press a key to end program"

'---Wait for a key press
WaitKey