For those of you curious about the finer details, here's a writeup from the viewer Daniel Flores justifying the final approximation: https://www.overleaf.com/read/wdzkfjbkwzyf
The fact that only primes that are one above a multiple of four can be expressed as the sum of two squares is known as "Fermat's theorem on sums of two squares": https://goo.gl/EdhaN2
Timestamps 0:00 - Introduction 1:39 - Counting lattice points 5:47 - Gaussian integers 10:30 - The lattice point recipe 17:50 - Counting on one ring 20:14 - Exploiting prime regularity 25:19 - Combining the rings 28:36 - Branches of number theory
Thanks to these viewers for their contributions to translations Hebrew: Omer Tuchfeld
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