From: Robin Chapman <rjc@maths.ex.ac.uk>
Subject: Re: Funny maths
Date: Wed, 05 Nov 1997 08:01:45 -0600

In article <63os3h$7sg$1@gannett.math.niu.edu>,
  rusin@vesuvius.math.niu.edu (Dave Rusin) wrote:
>
> In article <63ck92$1am@turner.efrei.fr>, Damien Wyart <wyart@efrei.fr> wrote:
> >
> >Making a stack of cubes, so that each side of the tower has the 4 different
> >colors. Here are the cubes :
> >
> > R      R      V      B
> > R      J      R      V
> >BRJ    BJR    BJJ    JRB
> > V      V      V      V
>
> This appears to be the puzzle marketed about 20-30 years ago under the
> name "Instant Insanity". Some comments may be found at
> 	http://www.math.niu.edu/~rusin/uses-math/games/other/insanity

A book which deals with this type of problem in a very nice way (togther
with the 12-coin problem which is such a regular visitor to these
newsgroups) is Puzzles and Paradoxes by T. H. O'Beirne published
originally by Oxford University Press in 1965 but reprinted by Dover in
1984.

Robin Chapman                           "256 256 256.
Department of Mathematics                O hel, ol rite; 256; whot's
University of Exeter, EX4 4QE, UK        12 tyms 256? Bugird if I no.
rjc@maths.exeter.ac.uk                   2 dificult 2 work out."
http://www.maths.ex.ac.uk/~rjc/rjc.html  Iain M. Banks - Feersum Endjinn