Mathieu Bouchard <matju / cam.org> wrote in
<Pine.LNX.3.96.1010206123024.4723B-100000 / relayer>: 

<<SNIP>>
>
>This series is almost an exponential of an exponential!
>

I am aware of this and I must clarify that the *algorithm* (factorial
combined with **2) was just "a playing around". 

<<SNIP>>
>Ruby's threading system is preemptive within Ruby code, but is
>cooperative at the C level.
>
>Operations on integers are atomic, that is, ininterruptible.
>

Here we go!

>The time it takes to kill depends on the speed of your machine. 
>Counterintuitively, the faster it is, the more time it takes to kill
>your thread.
>
Thanks
Clemens