Very nice post! Small comment: Ideally, big-O notation is for upper bounds. If you are doing lower bounds, you should ideally use big-Omega notation. But Omega

Very nice post! Small comment: Ideally, big-O notation is for upper bounds. If you are doing lower bounds, you should ideally use big-Omega notation. But Omegas are harder to format in plain text, so it may be better to abuse notation and use big-O...