Hint for Final Challenge:

Take any prime number greater than 3, square it and subtract one. Repeat several times and record your results.

What is the highest common factor of the numbers you get? How is this related to the observations you made when working on the building blocks?

Take any prime number greater than 3, square it and subtract one. Repeat several times and record your results.

What is the highest common factor of the numbers you get? How is this related to the observations you made when working on the building blocks?