I had to encode a factory's shift schedule. I noticed that it repeated in a regular way with each month. Then I noticed that there was yet another, more subtle

I had to encode a factory's shift schedule. I noticed that it repeated in a regular way with each month. Then I noticed that there was yet another, more subtle symmetry in between weeks, so I encoded that too. Then I realized the remaining pattern was a simple wavy line, so I replaced that part with a function based on a sine wave with the appropriate amplitude and period. In my defense, I was 16.