Astrologer's graph
This way of representing the 12 zodiacal "houses" is not only more
convenient than a simple divided circle but also more elegant.
This graph deserves a special respect among mathematicians.
Casting a horoscope to the richer members of the society
-- a rather complex arithmetical process --
was for ages a scientist's economical survival aid.
In a sense -- it made science possible!
See more diagrams.
The harmonic evolution
digraph consists of a single high tree: