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Topic: combinatorics in three dimensions: what is being enumerated?
Replies: 4   Last Post: Apr 4, 2013 4:07 AM

 Messages: [ Previous | Next ]
 David Bernier Posts: 3,892 Registered: 12/13/04
combinatorics in three dimensions: what is being enumerated?
Posted: Apr 3, 2013 6:26 AM

I'm counting something. What could it be?

000
001
010
011
100
101
110
111
============
Subtotal: 8

00*
0*0
*00
0*1
*01
01*
*10
*11
10*
1*0
1*1
11*
=============
Subtotal: 12

0**
**0
*0*
**1
*1*
1**
==============
Subtotal: 6

***
==============
Subtotal: 1

Now summarizing the above, where below star means also
asterisk, we get:

0-Star: 8
1-Star: 12
2-Star: 6
3-Star: 1
==========================
Grand Total: 27

Note: 3^3 = 27.

What could I be enumerating?

Clue given in the ROT13 substitution cipher:

pbhagvat gur snprf bs ulcrephorf eniv inxvy

David Bernier
--
\$apr1\$LJgyupye\$GZQc9jyvrdP50vW77sYvz1

Date Subject Author
4/3/13 David Bernier
4/3/13 Brian Q. Hutchings
4/3/13 fom
4/4/13 David Bernier
4/4/13 fom