Here's an example of a problem from an entirely different domain:

An error control coding scheme can correct up to 3 errors in the header of a packet and up to one error in the body of a packet. A given message is divided into four consecutive packets. Find all possible correctible distributions of 6 errors among the four packets, treating the order of the four packets as significant.

Phillip

On Mon, Sep 12, 2011 at 9:41 AM, Phillip M. Feldman <report@bugs.python.org> wrote:

Phillip M. Feldman <Phillip.M.Feldman@gmail.com> added the comment:

Hello Mark,

This is a fair question.  Suppose that I have three boxes with capacity
limits of 3, 2, and 1, and that there are three balls in total.  Two of the
possible distributions are the following:

2, 0, 1
2, 1, 0

Capacity limits of the individual boxes must be observed when distributing
the balls.  Even though the second and third boxes have different
capacities, we must treat the above two distributions of balls as
equivalent.

Combinatorics problems involving boxes with capacity limits arise in such
application domains as physics and reliability.

Phillip

On Mon, Sep 12, 2011 at 5:13 AM, Mark Dickinson <report@bugs.python.org>wrote:

>
> Mark Dickinson <dickinsm@gmail.com> added the comment:
>
> > "unlabelled balls in unlabelled boxes with capacity limits"
>
> What does this mean?  If the boxes are unlabelled, how can they have
> individual capacity limits?  Or do you mean just a single limit that applies
> to all boxes?
>
> ----------
> nosy: +mark.dickinson
>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <http://bugs.python.org/issue12961>
> _______________________________________
>

----------
nosy: +Phillip.M.Feldman@gmail.com
Added file: http://bugs.python.org/file23132/unnamed

_______________________________________
Python tracker <report@bugs.python.org>
<http://bugs.python.org/issue12961>
_______________________________________