A visual proof that
1/4 + 1/4² + 1/4³ + … = 1/3

⚪⚪⚪⚪⚪⚪⚪⚪
⚪⚫⚪⚪⚪⚪⚪⚪
⚪⚪⚫⚫⚪⚪⚪⚪
⚪⚪⚫⚫⚪⚪⚪⚪
⚪⚪⚪⚪⚫⚫⚫⚫
⚪⚪⚪⚪⚫⚫⚫⚫
⚪⚪⚪⚪⚫⚫⚫⚫
⚪⚪⚪⚪⚫⚫⚫⚫

— Fermat's Library (@fermatslibrary) July 21, 2019

And this one?@GeoGebra applet:https://t.co/2DG4d9Ldhlhttps://t.co/hbcj4armTc pic.twitter.com/Rdi4wlY0F2

— Ignacio Larrosa Cañestro (@ilarrosac) July 22, 2019