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From: Jeremy Sanders <jeremy@jeremysanders.net>
Subject: Re: A new module for performing tail-call elimination
Date: Thu, 16 Jul 2015 13:29:11 +0200
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Xref: csiph.com comp.lang.python:93924

Robin Becker wrote:

> I believe the classic answer is Ackermann's function
> 
> http://demonstrations.wolfram.com/RecursionInTheAckermannFunction/
> 
> which is said to be not "primitive recursive" ie cannot be unwound into
> loops; not sure whether that implies it has to be recursively defined or
> can perhaps be broken down some other way. For more eye-glazing

But am I right in thinking that TCO doesn't work for Ackermann's function, 
at least not as it's written down in the above page?

J.