piano scale
E♭ Lydian
E♭1F2G3A♯4B♭5C6D7
Major with a raised fourth. The fourth mode of the major scale.
The same sounds spelled from the other side are D♯ Lydian.
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
E♭WFWGWAHB♭WCWDHE♭
What is true of it
E♭ Lydian is E♭, F, G, A, B♭, C and D, and back to E♭.
Its steps are W – W – W – H – W – W – H, where W is a whole step and H a half.
On the same tonic, E♭ major differs from it by exactly one note.
Chords made only of these notes
Found by testing every chord in the catalogue against these 7 sounds, not chosen.