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Ponder This

April 2016

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Ponder This Challenge:

Let p(x)=x**3-300*x**2+a*x+b be a cubic polynomial with unknown parameters a and b that has three positive integers roots.
Based on the surprising fact that cats falling from lower floors have been found to suffer greater injury than those falling from higher floors (, IBM has built a robo-cat that when experimentally dropped from a height of n stories will either disintegrate (if p(n)>=0), or leave the experiment exactly the same way it entered it (if p(n)<0).

If you have only seven such robo-cats, find an algorithm to predict the fate of a fall from every floor with no more than 16 experiments.

No (robo)cats were harmed while preparing this challenge :-)

We will post the names of those who submit a correct, original solution! If you don't want your name posted then please include such a statement in your submission!

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Challenge: 30/03/2016 @ 12:00 PM EST
Solution: 01/05/2016 @ 12:00 PM EST
List Updated: 1/05/2016 @ 12:00 PM EST

People who answered correctly:

Dan Dima (30/03/2016 10:55 PM IDT)
Benjamin Lui (31/03/2016 09:39 PM IDT)
Yan-Wu He (01/04/2016 06:19 AM IDT)
Zoltán Haindrich (01/04/2016 04:14 PM IDT)
James Dow Allen (01/04/2016 05:45 PM IDT)
Liubing Yu (01/04/2016 09:36 PM IDT)
Uoti Urpala (02/04/2016 10:59 AM IDT)
Florian Fischer (02/04/2016 04:07 PM IDT)
Jeffrey Boyle (03/04/2016 05:11 AM IDT)
Sergey Koposov (04/04/2016 08:16 PM IDT)
Erik Hostens (04/04/2016 10:28 PM IDT)
Paolo Farinelli (05/04/2016 04:28 AM IDT)
Don Dodson & David Dodson (06/04/2016 07:21 AM IDT)
Bert Dobbelaere (06/04/2016 09:17 PM IDT)
Motty Porat (06/04/2016 11:54 PM IDT)
Jimmy Waters (10/04/2016 12:34 AM IDT)
Shirish Chinchalkar (10/04/2016 05:54 PM IDT)
Raymond Lo (12/04/2016 02:45 PM IDT)
Chris Shannon (14/04/2016 03:50 AM IDT)
Hafsteinn Einarsson (17/04/2016 07:01 PM IDT)
Di Luo (18/04/2016 08:51 AM IDT)
Arnab Bose (18/04/2016 07:52 PM IDT)
Hossein Boomari & Hamidreza Bidar (19/04/2016 07:27 PM IDT)
David F H Dunkley (22/04/2016 02:34 AM IDT)
Hendrik Nigul (25/04/2016 04:29 PM IDT)
Guillem Collell Talleda (25/04/2016 04:44 PM IDT)
Shouky Dan & Tamir Ganor (26/04/2016 04:48 PM IDT)
Hao Zheng (29/04/2016 12:45 AM IDT)
David Greer (30/04/2016 04:00 PM IDT)
Radu-Alexandru Todor (01/05/2016 04:09 PM IDT)
Adrian Neacsu (01/05/2016 07:11 PM IDT)