From: jbb@notatt.com   
      
   Richard Fateman wrote on 6/23/2018 7:23 PM:   
   > On Saturday, June 23, 2018 at 5:34:27 PM UTC-7, S.K.R. de Jong wrote:   
   >> Are there any symbolic systems that can deal with Ackermann   
   >> functions computations?   
   >   
   > Can you be more specific on what you mean by "deal"?   
   >   
   > It is not especially symbolic. The obvious definition   
   > usually causes problems   
   > with stack space because it is a heavily-recursive function.   
   >   
   > Symbolic systems also use stack space, so they suffer the   
   > same fate.   
   >   
   >   
   >   Here's a definition in lisp.   
   >   
   > (defun ackermann (x y)   
   >    (cond ((= y 0) 0)   
   >          ((= x 0) (* 2 y))   
   >          ((= y 1) 2)   
   >          (t (ackermann (- x 1) (ackermann x (- y 1))))))   
      
   I remember a note a million years ago in either CACM or the British   
   Computer Journal that showed how to compute any A(n,m), where 0<=n<=N   
   and 0<=n<=M, in space proportional to NxM. This was done in Algol and   
   used an array of dimension NxM. I know that this has little to do with   
   the original question but thought I'd share the memory.   
   --   
   Jeff Barnett   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)