All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Numbers
DIY prime magic (Posted on 2012-01-13) Difficulty: 4 of 5
In a 4x4 magic square all rows, columns and the two main diagonals are distinct 4-digit prime numbers when read in either direction.

Create such a square.

Bonus (d4): same for order-5 magic square and 5-digit primes.

Based on L. E. Card,Patterns in Primes, JRM 1:2, 1968, pp .93-99,

See The Solution Submitted by Ady TZIDON    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
re: From the computer -semi-spoiler | Comment 7 of 10 |
(In reply to From the computer -semi-spoiler by brianjn)

Since my comment at that location re 5-order Q-Basic compilation I have a program running, been going for 24 hours and still hasn't offered a result.
My computer is currently offering:
1 1 1 9 7
1 0 0 0 7
3 3 6 1 7
* * * * *
* * * * *

The program is working upwards so there is no guarantee that the three primes, which are also reversible, will be intact.
Oops 3 3 6 2 3 !

I think the compiled program has a finish within our life time, but I'll try to let it run for 7 days to see if there is an outcome.

That said, I look at the date Ady gave as reference, 1968! One must ask how the solutions he has telegraphed in comments came into being, computers were still big but just how powerful?



  Posted by brianjn on 2012-01-19 08:11:29

Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (11)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information