I hate to beat a dead horse, but isn't this solution the same as
the one that was offered up by an Andy?, ie.

        a/3 = a/2 - a/4 + a/8 ...

        Matt

On Mon, 16 Mar 1998, Lauri Pirttiaho wrote:

> The most accurate approximate arithmetic is done by using
> convergent iteration.
>
> An iteration to divide by 3 is based on the identity
>
> a/3=a/2-(1/2)(a/3)
>
> Approximate a/3 by a/2 and repeat
>
> (new a/3) = a/2 - (old a/3) /2.
>
> until (new (new a/3)) == old a/3
>
> The iteration converges rather fast.
>
> Notice that you need to compare results over two iterations
> to "filter" the last bit oscillation.
>
> In the same way you can divide by 5 by iteration based on
> identity
>
> a/5=a/4-(1/4)(a/5)
>
> etc.
>
> -- Lauri
>
> ---
> <a href="http://www.ee.oulu.fi/~lapi/">For more info.</a>
>

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/* Matt Calder, Dept. of Statistics, CSU */
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