Number Scrabble

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Number Scrabble (also known as Pick15 [1] [2] [3] or 3 to 15 [4] ) is a mathematical game where players take turns to select numbers from 1 to 9 without repeating any numbers previously used, and the first player to amass a personal total of exactly 15 wins the game. [5] [6] The game is isomorphic to tic-tac-toe, as can be seen if the game is mapped onto a magic square. [6]


A 3x3 magic square of the numbers 1 through 9 Magicsquareexample.svg
A 3x3 magic square of the numbers 1 through 9

Number Scrabble is played with the list of numbers between 1 and 9. Each player takes turns picking a number from the list. Once a number has been picked, it cannot be picked again. If a player has picked three numbers that add up to 15, that player wins the game. [5] [6] [7] However, if all the numbers are used and no player gets exactly 15, the game is a draw. [5] [6]

The game is identical to tic-tac-toe, as can be seen by reference to a 3x3 magic square: if a player has selected three numbers which can be found in a line on a magic square, they will add up to 15. If they have selected any other three numbers, they will not. [8]

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