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,

(In reply to re(3): From the computer -semi-spoiler by Charlie)

I saw this only after responding to your email in which I did make a note that I had implemented the square root concept, but I hadn't gone further.


The SUB primetest code was an abridgement of code offered @ http://javascriptsource.com/math-related/prime-number.html
which did test everything.

Posted by brianjn on 2012-01-21 20:39:19