Written out
Every accidental is written in, rather than left to a key signature, so the letters can be read one at a time.
The step pattern
CW+HE♭WFHG♭HGW+HB♭WC
What is true of it
C blues is C, E♭, F, G♭, G and B♭, and back to C.
Its steps are W+H – W – H – H – W+H – W, where W is a whole step and H a half.
Across the first twelve frets of the ukulele its notes fall in 26 places, which is what makes a scale a shape rather than a list.
Chords made only of these notes
Found by testing every chord in the catalogue against these 6 sounds, not chosen.
Other scales on C
C major pentatonicpentatonicC minor pentatonicpentatonicC major bluespentatonicC majormajorC natural minorminorC harmonic minorminor
C♯ bluesD♭ bluesD bluesD♯ bluesE♭ bluesE bluesF bluesF♯ bluesall 374