International Records of Bimagic Squares and the Structure Method

Since the first bimagic squares invented by G.Pfeffermann in 1890 so far,the magicsquare has god unparalleled development.Magic square amateurs in our country have actively fore,thus pushing the study of magic squares forward greatly.In 3m-order,4m-order,5m-order and 7m-order bimagic squares,the maximal structural degree of difficulty is 3m order bimagic square.By making use of the placement of magic squares and the known bimagic square composition,SU Maoting and GAO Zhiyuan have successfully structured 30-order,33-order,39-order,42-order,51-order,54-order,57-order bimagic squares.