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.
L. E. Card,Patterns in Primes, JRM 1:2, 1968, pp .93-99,
(In reply to re(2): From the computer -semi-spoiler
Of course it wouldn't be a Latin square, having a complete set of 4 chosen digits in each row or column, but "magic" implied constant sums.
In fact a normal magic square can't be a Latin square as none of the digits would be repeated, whereas in a Latin square each would be repeated as many times as there are rows.
Wikipedia article here.
The only exception the article makes to the constant-sum rule is for some word squares rather than number squares. It would seem the wording is misleading. I restricted my search to only those sets of reversible primes that had the same sum of digits.
Posted by Charlie
on 2012-01-14 11:31:56