2016-07-09 Circle/Square Optical Illusion via @algoritmic ART Make a Sugihara Circle/Square Optical Illusion Out of Paper https://divisbyzero.com/2016/07/06/make-a-sugihara-circlesquare-optical-illusion-out-of-paper/ Sugihara’s Circle/Square Optical Illusion https://divisbyzero.com/2016/07/05/sugiharas-circlesquare-optical-illusion/ 柱の錯覚に関する数式や展開図 (PDF)