C♯ major pentatonic

C♯1D♯2E♯3G♯5A♯6

The major scale without its two half steps. Five notes, and no pair of them a half step apart.

The same sounds spelled from the other side are D♭ major pentatonic.

Written out

Fig. 2 · C# major pentatonic, ascending

Every accidental is written in, rather than left to a key signature, so the letters can be read one at a time.

C♯WD♯WE♯W+HG♯WA♯W+HC♯

C♯ major pentatonic is C♯, D♯, E♯, G♯ and A♯, and back to C♯.

Its steps are W – W – W+H – W – W+H, where W is a whole step and H a half.

Across the first twelve frets of the ukulele its notes fall in 20 places, which is what makes a scale a shape rather than a list.

Found by testing every chord in the catalogue against these 5 sounds, not chosen.