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Topic: A certain type of matrix: any name or applications?
Replies: 3   Last Post: Mar 27, 2009 5:30 AM

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 jw12jw12jw12@yahoo.com Posts: 38 Registered: 10/27/05
A certain type of matrix: any name or applications?
Posted: Mar 17, 2009 2:01 PM

Is there a name for the following type of matrix (probably not) , or
(more possibly) some context or application where they appear?

(1) each entry is 1, 0, or -1
(2) the entries in each row add to 1
(3) each column vector only occurs once, and no column and its
negative both appear.
(4) the zero vector is not allowed as a column

For example, if there are two rows the matrices
1 -1 0
1 0 -1
and
1 -1 0
-1 0 1
satisfy the conditions.
For n rows I believe the maximum number of columns is 3^(n-1) and
there is a simple recursive procedure to generate a matix of this size
that satisfies the conditions.

Thanks
jw

Date Subject Author
3/17/09 jw12jw12jw12@yahoo.com
3/18/09 Robert Israel
3/18/09 jw12jw12jw12@yahoo.com
3/27/09 H.Oe.