Sum of the first odd numbers

Author:
Vincent Pantaloni
Topic:
Addition, Numbers, Sequences and Series

GIF

GIF

What is this ?

This is an original visual proof that : The sum of the 1st n odd numbers is equal to n². 1+3+5+...+(2n-1)=n².

ggb applet

Bigger GeoGebra applet with spheres

GIF (HD)

GIF (HD)

Reboot of an older (bigger) version :

https://www.geogebra.org/m/mt8apr5e

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