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A puzzle based on combinatorics, which is the study of counting discrete structures.

For example, how many ways to arrange $3$ of $abcd$, where order is important?

We have $abc,abd,acd,bcd$ and six of each (for example $abc,acb,bac,bca,cab,cba$), and so the answer is $24$.

For elementary combinatoric explanations, see:

• Wikipedia
• Mathigon
• Brilliant
• Maths is Fun

Puzzles where permutations, sets, graphs, lattices and other combinatorial mathematics feature prominently should include this tag.

A puzzle based on combinatorics, which is the study of counting discrete structures.

For example, how many ways to arrange $3$ of $abcd$, where order is important?

We have $abc,abd,acd,bcd$ and six of each (for example $abc,acb,bac,bca,cab,cba$), and so the answer is $24$.

For basic combinatoric examples and explanations, see:

• Wikipedia
• Mathigon
• Brilliant
• Maths is Fun

Puzzles where permutations, sets, graphs, lattices and other combinatorial mathematics feature prominently should include this tag.

A puzzle based on combinatorics, which is the study of finite or countable discrete structures. Puzzles where permutations, sets, graphs, lattices, or combinatorial mathematics feature prominently should typically include this tag.

Example: In the wheat and chessboard problem, one places one grain of wheat on the first square, two on the second, four on the third, and so on (doubling the number of grains on each subsequent square). How many grains of wheat would be on the chessboard at the finish?

A puzzle based on combinatorics, which is the study of counting discrete structures.

For example, how many ways to arrange $3$ of $abcd$, where order is important?

We have $abc,abd,acd,bcd$ and six of each (for example $abc,acb,bac,bca,cab,cba$), and so the answer is $24$.

For elementary combinatoric explanations, see:

• Wikipedia
• Mathigon
• Brilliant
• Maths is Fun

Puzzles where permutations, sets, graphs, lattices and other combinatorial mathematics feature prominently should include this tag.

A puzzle based on combinatorics, which is the study of finite or countable discrete structures. Puzzles where permutations, sets, graphs, lattices, or combinatorial mathematics feature prominently should typically include this tag.

A puzzle based on combinatorics, which is the study of finite or countable discrete structures. Puzzles where permutations, sets, graphs, lattices, or combinatorial mathematics feature prominently should typically include this tag.

Example: In the wheat and chessboard problem, one places one grain of wheat on the first square, two on the second, four on the third, and so on (doubling the number of grains on each subsequent square). How many grains of wheat would be on the chessboard at the finish?