Why do the sines of the numerators of $\pi$’s continued fraction convergents approach zero?

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I was messing with the sine function and tried getting values close to zero with integer inputs. I found a peculiar pattern. If you take pi’s continued fraction and write them out as one whole fraction, and take the numerators, you get the sequence here: http://oeis.org/A046947. If you take the sin (radians) of this sequence, you get values very very close to zero. For example, if you take the last listed number on oeis, the sin is only -2*10^-14. Is there any reason as to why this happens?

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Most denominators $q$ will get you a fraction $p/q$ that is within $1/2q$ of $\pi$. A convergent will get you a fraction within $1/q^2$. So $p$ is within $1/q$ of $q\pi$, and its sine is very small.