Warning: this won't work on some browsers, especially mobile, though in my experience you can generate the audio (without hearing it) and then listen to the recording.
(The keyboard doesn't work while the beat isn't playing. Also it'll end eventually, and then you have to refresh the page.)
This element will store the audio after you press pause. You can then save it as a file by right clicking.
This is an experiment of key patterns with a ratio of φ. The music is made of long and short beats according to the Fibonacci word: long short long, long short, long short long. long short long, long short. etc. You can then think of the music as having long and short measures that follow that same pattern.