Set, the card game: Difference between revisions

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Why does <code>isset</code>, the word that tests if three cards constitute a set, use <code>+</code> and <code>mod</code>?
Why does <code>isset</code>, the word that tests if three cards constitute a set, use <code>+</code> and <code>mod</code>?


If we map any of the properties, say colour, onto the numbers 0, 1 and 2, then the sum of three colours mod 3 is 0 if and only iff all the colours are different or all the colours are the same. This can be confirmed exhaustively, or for the underlying mathematics see the first two paragraphs of the section "A Mathematical Perspective" (pages 7 and 8) in this paper:
If we map any of the properties, say colour, onto the numbers 0, 1 and 2, then the sum of three colours mod 3 is 0 if and only if all the colours are different or all the colours are the same. This can be confirmed exhaustively, or for the underlying mathematics see the first two paragraphs of the section "A Mathematical Perspective" (pages 7 and 8) in this paper:


::[https://web.math.princeton.edu/~charchan/SET.pdf SETs and Anti-SETs: The Math Behind the Game of SET, by Charlotte Chan]
::[https://web.math.princeton.edu/~charchan/SET.pdf SETs and Anti-SETs: The Math Behind the Game of SET, by Charlotte Chan]
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