If curious, past threads:

Drawing Spirograph curves in Python - https://news.ycombinator.com/item?id=17883187 - Aug 2018 (10 comments)

Spirograph Simulator (2014) - https://news.ycombinator.com/item?id=13256222 - Dec 2016 (40 comments)

Spirograph drawing - https://news.ycombinator.com/item?id=11026525 - Feb 2016 (1 comment)

Spirograph: Circles on circles rotating in opposite directions - https://news.ycombinator.com/item?id=6959404 - Dec 2013 (1 comment)

Spirograph in HTML 5 - https://news.ycombinator.com/item?id=5505467 - April 2013 (20 comments)

The mathematics of spirograph art - https://news.ycombinator.com/item?id=3777536 - March 2012 (2 comments)