Ulam's game
Ulam's game is a game where you start with a big grid of numbers, and you choose a number to start with. Then, you cross out all the numbers in the grid that can be made by multiplying your starting number by any other number in the grid.
For example, if you started with the number 2, you would cross out 4, 6, 8, 10, and so on, because they are all made by multiplying 2 by some other number.
After you cross out all those numbers, you choose another number that hasn't been crossed out yet, and you repeat the process until there are no more numbers that haven't been crossed out.
The goal of the game is to cross out as many numbers as you can, because the person who crosses out the most numbers wins.
Ulam's game is a fun way to learn about prime numbers (numbers that can only be divided by 1 and themselves), because the numbers that can't be crossed out are all prime numbers.
For example, if you started with the number 2, you would cross out 4, 6, 8, 10, and so on, because they are all made by multiplying 2 by some other number.
After you cross out all those numbers, you choose another number that hasn't been crossed out yet, and you repeat the process until there are no more numbers that haven't been crossed out.
The goal of the game is to cross out as many numbers as you can, because the person who crosses out the most numbers wins.
Ulam's game is a fun way to learn about prime numbers (numbers that can only be divided by 1 and themselves), because the numbers that can't be crossed out are all prime numbers.
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