“Geometry of Circles” is a series of animated shorts created for Sesame Street in 1979 with music by Philip Glass.

From the Muppet Wiki:

The shorts consist of the movement of six circles (each with a different color of the rainbow) that are formed by and split up into various geometric patterns. Glass’s music underscores the animation in a style that closely resembles the “Dance” numbers and the North Star vignettes written during the same time period as his Einstein on the Beach opera.

Below, all four of the “Geometry of Circles” animations produced by Glass and The Children’s Television Workshop: