An addition-multiplication square is a square of integers that is simultaneously a magic square and multiplication magic square. In 1955, Horner found a square of order eight with addition magic constant 840 and multiplicative magic constant 2058068231856000, and largest number 261 (left figure; Horner 1955, Hunter and Madachy 1975). In 2005, Boyer found a smaller order-eight square above with addition constant 600, multiplicative constant 67463283888000, and largest number 225. Boyer also found a square with smaller multiplicative constant 51407948592000, but larger addition constant (760) and largest number (333).
We guarantee you’ll find the right tutor, or we’ll cover the first hour of your lesson.