The sum of cubes has a beautiful and surprising relationship to the triangle numbers. This videos proves this relationship in a visual and intuitive way. If you prefer reading, I've written a blog post on the same topic: https://penguinmaths.blogspot.com/2019/07/the-sum-of-cubes-and-triangle-numbers.html There is a small mistake at the end of the video, when substituting 1,000,000 into the equation, I accidentally treated 2n^3 as (2n)^3. My bad!