www.multimagie.com/indexengl.htm: an update is now online, click on “News of January 2010” Among the news you will see that my 5 enigmas of 2008 are still unsolved! And several news on additive-multiplicative magic squares, magic when you add the cells, and still magic when you multiply the cells: - a new 6th enigma, construct a 5x5 add-mult square - several new add-mult squares including my big 1024x1024 square, its magic sum is 274878169600, but its magic product has 8356 digits... kindly checked by two persons of [math-fun], thanks to Joshua Zucker and W. Edwin Clark - J. Dénes / A. D. Keedwell / P. Erdös had already posed in 1974 the problem on the possible add-mult squares - help needed, any person having some biographical info on the first author of this kind of squares: Walter W. Horner, Pittsburgh??? Direct access to the unsolved enigmas: www.multimagie.com/English/Enigmas.htm Christian.