5
$\begingroup$

enter image description here

  151  131 359 131  151
    \   ^   ^   ^ /
  131 < 1   3   1 > 131
  353 < 3   5   3 > 353
  191 < 1   9   1 > 191
    /   V   V   V \  
  151  131 953 131  151

This 3x3 table have an interesting properties.
Every direction (up,down, Right, Left, 45°,135°,225°,315°) of 3 cell form prime numbers.
There are 6 unique prime numbers from this table, they are 131, 151, 191, 353, 359, 953.

Create a more interesting 3x3 table with the same rule, which there are 9 unique prime numbers from the table.

Improve this question
$\endgroup$
2
  • 1
    $\begingroup$ ^vote with a note: Great variation on magic squares. Just a matter of time before someone looks at one or two OEIS pages. $\endgroup$
    – humn
    Nov 2, 2016 at 5:45
  • 1
    $\begingroup$ @humn : Every one can use those OEIS pages, then take 9 3-digit-numbers from those numbers to form the table. $\endgroup$
    – Jamal Senjaya
    Nov 2, 2016 at 5:57

1 Answer 1

Reset to default
2
$\begingroup$

The solution -

  151  971 751 113  953
    \   ^   ^   ^ /
  311 < 1   1   3 > 113
  157 < 7   5   1 > 751
  179 < 9   7   1 > 971
    /   V   V   V \
  359  179 157 311  151

unique primes:

157 311 359 113 151 953 179 751 971

The 3 mirror equivalents (left/right, top/bottom, and corner/corner) also work.
Beyond these, there are no other solutions.

Improve this answer
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.