And this is why analog audio is better than digital.
With analog, the sine wave is what is reproduced and what you hear.
With digital, what you get is that blocky dashed line.
You end up losing a lot of the nuances.
It's not actually that simple (or right as it is written). The first wave is right, the second is actually the first formula plus the second, the third is the sum of the first three, etc. It approaches a square wave as you add more harmonics (higher frequencies that are multiples of the first - the 3@, 5@, 7@).
With analog, the sine wave is what is reproduced and what you hear.
With digital, what you get is that blocky dashed line.
You end up losing a lot of the nuances.