Domino Magic Square
Consider a small set of dominoes with only one, two, or three dots
on each side. A full set then contains only six
dominoes: 1-1, 1-2, 1-3, 2-2, 2-3, 3-3. Take one full set plus
two duplicate dominoes from a second set. Lay the eight dominoes into a
four-by-four grid such that the sum of the dots in any row, column,
or major diagonal is the same. You may choose any two dominoes
from the second set, as long as they are different.
I know of solutions for at least two different pairs of duplicate
dominoes.
Source: Original. Used in "Ken's Puzzle of the Day" March 2, 1995
Solution
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