There are ways to make a necklace using beads of colors, with being the totient function. Build and wear them all!
Contributed by: Michael Trott with permission of Springer (March 2011)
From: The Mathematica Guidebook for Numerics, second edition by Michael Trott (© Springer, 2008).
Open content licensed under CC BY-NC-SA
Wolfram Demonstrations Project
Published: March 7 2011