A kusa da 265 AD, Wei Kingdom masanin lissafi Liu Hui ya kirkiro wani polygon-tushen iterative algorithm kuma yayi amfani da shi tare da 3,072-gefe polygon don samun darajar π na 3.1416. Daga baya Liu ya ƙirƙiri wata hanya mafi sauri na lissafin π kuma ya sami darajar 3.14 tare da polygon mai gefe 96, ta hanyar amfani da gaskiyar cewa bambance-bambance a cikin yanki na polygons masu biye suna samar da jerin lissafi tare da kashi na 4. Masanin lissafin kasar Sin Zuongzhi, a kusa da 480 AD, ya kiyasta cewa 3.159 π < 0.146 π (100 AD, kimanin 3.1623), da kuma 142/45 (karni na 3,153 π = 3.155/3.159 π...), wanda ya yi amfani da lissafin lissafi na Faransanci da Faransanci da Faransanci.
9 da kuma