I’m doing something that I should have done a long time ago: collecting a series of posts into one single post. The following links comprised my series on the 2016 Pizza Hut Pi Day Challenge.
Part 1: Statement of the problem.
Part 2: Using the divisibility rules for 1, 5, 9, 10 to reduce the number of possibilities from 3,628,800 to 40,320.
Part 3: Using the divisibility rule for 2 to reduce the number of possibilities to 576.
Part 4: Using the divisibility rule for 3 to reduce the number of possibilities to 192.
Part 5: Using the divisibility rule for 4 to reduce the number of possibilities to 96.
Part 6: Using the divisibility rule for 8 to reduce the number of possibilities to 24.
Part 7: Reusing the divisibility rule for 3 to reduce the number of possibilities to 10.
Part 8: Dividing by 7 to find the answer.