4:5:6 is the classical major triad, also known as the Ptolemaic major triad, or imprecisely as the just major triad. It is the most consonant of all the just intonation triads.

Chord information
Harmonics 4:5:6
Subharmonics 1/(15:12:10)
Intervals from root 1/15/43/2
Cents from root 386¢702¢
Step intervals 5/4, 6/5
Step cents 386¢, 316¢
Color name yo or y
Prime limit 5
Genus 35 (15)
Intervallic odd limit 5
Otonal odd limit 5
Utonal odd limit 15
Consistent edos (d ≥ 2) 3edo*, 12edo*, 15edo*, 19edo**, …

Common tetrads based on this triad (5-limit except where noted):