Notes: C, D, E, F, Gb, G, A, and B - Key: C - Category: Nonatonic or Ennatonic Scales
The C Major/Lydian mixed uses nine notes per octave. Because of this same reason it is a member of the so called Nonatonic or Ennatonic -scales that have Nine-note (or Nine-tone). On the piano keyboard, it is made up of one black keys: Gb and seven white keys: C, D, E, F, G, A, and B. This combination makes this scale - as well as the C Prometheus, C Prometheus Liszt, and C Prometheus Neapolitan - as great choices for composing or improvising music.
If we take a look a the key signature of the C Major/Lydian mixed Scale we can find it has one flats and no sharps. Therefore, on sheet music you will find one accidentals on the score. The notes of this scale are: C, D, E, F, Gb, G, A, and B.