November 2019 - Challenge

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This month's challenge is from Hugo Pfoertner (thanks!).
Find a 9x9 matrix that contains the digits 1..9, in which each digit appears exactly nine times, whose determinant is at least the hexadecimal number 0x3704d007 (LOOPhOLE upside down in hexadecimal).
A known simple solution uses Latin squares. However, we're looking for solutions that lead to values of the determinant other than those that can be achieved with Latin squares. A bonus '*' will be awarded to the best solution and '**' if you solve the open question of finding a solution that beats the record determinant found with Latin squares.



We will post the names of those who submit a correct, original solution! If you don't want your name posted then please include such a statement in your submission!

We invite visitors to our website to submit an elegant solution. Send your submission to the ponder@il.ibm.com.

If you have any problems you think we might enjoy, please send them in. All replies should be sent to: ponder@il.ibm.com

Challenge: 5/11/2019 @ 12:00 PM EST
Solution: 03/12/2019 @ 12:00 PM EST
List Updated: 05/11/2019 @ 12:00 PM EST

People who answered correctly:

**Oleg Vlasii (07/11/2019 10:49 PM IDT)
Daniel Scheinerman (08/11/2019 08:39 PM IDT)
Anders Kaseorg (08/11/2019 10:55 PM IDT)
Richard Gosiorovsky (09/11/2019 06:11 PM IDT)
Deron Stewart (09/11/2019 11:40 PM IDT)
Bert Dobbelaere (11/11/2019 08:30 PM IDT)
George Lasry (12/11/2019 03:43 PM IDT)
Collin Pearce (12/11/2019 08:45 PM IDT)
Benjamin Buhrow (12/11/2019 10:45 PM IDT)
Thomas Huet & Eden Saig (14/11/2019 08:51 PM IDT)
Daniel Bitin (15/11/2019 03:41 PM IDT)
Willem Hendriks (16/11/2019 11:36 PM IDT)
Andreas Stiller (17/11/2019 11:09 PM IDT)
Thomas Egense (18/11/2019 09:00 AM IDT)
Deane Stewart (20/11/2019 06:35 AM IDT)
Stéphane Higueret (21/11/2019 06:25 PM IDT)
Amos Guler (21/11/2019 08:41 PM IDT)
Uoti Urpala (22/11/2019 06:30 AM IDT)
David Greer (22/11/2019 08:59 AM IDT)
**Andreas Knüpfer (24/11/2019 06:53 PM IDT)
Vivek Nema (26/11/2019 08:56 AM IDT)
Tom Chen (26/11/2019 03:58 PM IDT)
Alper Halbutogullari (26/11/2019 04:10 PM IDT)
Omer Shechter & Nir Lavee (28/11/2019 01:35 PM IDT)
Lorenz Reichel (30/11/2019 02:01 PM IDT)
Albert Stadler (30/11/2019 06:38 PM IDT)
**Oscar Volpatti (30/11/2019 10:16 PM IDT)
JJ Rabeyrin (30/11/2019 11:26 PM IDT)
Radu-Alexandru Todor (01/12/2019 02:19 AM IDT)
Bertram Felgenhauer (01/12/2019 02:29 AM IDT)
Florian Fischer (01/12/2019 02:56 AM IDT)
Li Li (01/12/2019 07:56 AM IDT)