The bass line from Pachelbel's Canon in D. This image was created with GNU LilyPond and post-processed with GraphicConverter. Here's the LilyPond source I used:
\version "2.4.2"
tune = \relative c {
\clef bass
\key d \major
\time 4/4
d2 a b fis
g2 d g a
}
\score {
\new Staff \tune
\layout { raggedright = ##t }
}
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