Versatile

Posted in Science & Math by Greg Ross on April 13th, 2007

What’s unusual about this magic square?

18 99 86 61
66 81 98 19
91 16 69 88
89 68 11 96

It works just as well upside down:

96 11 89 68
88 69 91 16
61 86 18 99
19 98 66 81