A Geometric Proof of the Square Pyramidal Number Formula

The pyramidal numbers 1, 5, 14, 30, … are the sums of the square numbers, . This Demonstration shows a geometric proof of the square pyramidal number formula, . In the figure the six pyramids of side length form an cuboid.

SNAPSHOTS

  • [Snapshot]
  • [Snapshot]
  • [Snapshot]
    • Share:

Embed Interactive Demonstration New!

Just copy and paste this snippet of JavaScript code into your website or blog to put the live Demonstration on your site. More details »

Files require Wolfram CDF Player or Mathematica.