Related: Check out my intro to oud (in Arabic)

octaves

The above can be produced with the following lilypond code

\score {
\new Staff \relative c' {
g4 a b c d e f g a b c d e f g
}
\layout {
ragged-right = ##t
\context {
\Staff
}
}
}

to remove the bars and and color the G note:

\score {
\new Staff \relative c' {
\override NoteHead.color = #(x11-color "LimeGreen")g4\override NoteHead.color = #(x11-color "Black") a b c d e f\override NoteHead.color = #(x11-color "LimeGreen") g\override NoteHead.color = #(x11-color "Black") a b c d e f\override NoteHead.color = #(x11-color "LimeGreen") g
}
\layout {
ragged-right = ##t
\context {
\Staff
\omit TimeSignature
%\omit BarLine
\remove "Bar_engraver"
}
}
}

octavesg

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