Find the number of ways in which the nine digits 1,2,3,...,9 can be arranged in a 3*3 square array such that the determinant of this square is an odd integer. Each digit to be used only once.
(In reply to
re: Computer Solution by Charlie)
I found the error in my program. A fixed version agrees with Larry's results.
The method Matlab used to get determinants sometimes resulted in numbers just a little off from their true integral value--not even enough to display as other than integers, but enough so the value mod 2 was not 1, even though it should have been. Rounding each of the values returned by the det function made the results agree with Larry's.
The count of 381 unique values was the resullt of a true -1 and a slightly-off -1 both being counted.
Edited on May 29, 2024, 4:19 pm
|
|
Posted by Charlie
on 2024-05-29 16:18:03 |
re(2): Computer Solution
