The only thing i read about a thing discovered in 150 A.D and concerning mathematics is here :
Mathematics (Rome Reborn: The Vatican Library & Renaissance Culture)
just read Ptolemy, Almagest in the middle of the page...
Another link concerning Ptolemy theorem
Crop circles: Hawkins 4
You can read more about diatonic circles and diatonic ratio following links in the same page.
And maybe the word you are looking for could be
diatonic circles.
Waow !! I'm not a pro in English but this theorem is really interesting !!
I hope it can help you...
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