Factor 9 grid
Factor 9 grid is a type of musical scale which was first proposed for esoteric reasons, as a supposed replacement to 12edo's irrational nature which was purported to have negative properties for humanity, and a switch to just intonation was supposed to fix them.
The scale goes as follows, in Hertz: 126, 135, 144, 153, 162, 171, 180, 189, 198, 207, 216, 225, 234, 252 (octave). However, since the esoteric affliction towards the note A being 432 Hz is usually considered, the scale is supposed to be played starting with A, which leaves a wide displacement inside the octave.
Factor 9 Grid temperament (495 & 666)
Subgroup: 2.3.5.7.11.13.17.19.23
Comma list: 442/441, 715/714, 2300/2299, 3060/3059, 3179/3174, 9025/9009, 57375/57344
POTE Generator: 63.0631c (~27/26)
Vals: 171f, 495, 666