The absurd circle division pattern explained | Moser’s circle problem

The absurd circle division pattern explained | Moser's circle problem

An apparent pattern that breaks, and the reason behind it.
Summer of math exposition:
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For the long-time viewers among you, if this sounds familiar, it’s because it’s a remake of one of the earliest videos on the channel. It’s such a wonderful problem, and the audio/pacing in earlier videos was really suboptimal, so I wanted to freshen it up a little here.

0:00 – The pattern
2:20 – Counting chords
4:03 – Counting intersection points
6:20 – Euler’s characteristic formula
11:30 – Connection with Pascal’s triangle
15:10 – Reflections
15:55 – SoME3


These animations are largely made using a custom python library, manim. See the FAQ comments here:

You can find code for specific videos and projects here:

Music by Vincent Rubinetti.

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3blue1brown is a channel about animating math, in all senses of the word animate. And you know the drill with YouTube, if you want to stay posted on new videos, subscribe:

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