古い現代音楽の巨匠リゲティの数学向け楽曲「Volumina」を聴きつつ、数理的な円の戯れに耳をすまそう。 $$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$ 今回はスタイナーの定理などでおなじみの「反転」をもち…