A Diminished (half-whole)

A Diminished (half-whole): A B♭ B# C# D# E F# G. Formula 1 ♭2 ♯2 3 ♯4 5 6 ♭7. Same notes as C Diminished (half-whole), E♭ Diminished (half-whole), F# Diminished (half-whole). Half and whole steps in turn, starting with a half step: the scale jazz players use over dominant chords with ♭9 and ♯9. It repeats every minor 3rd.