Hey, kids! Sudoku (which is Japanese for "I broke the cup on Wednesday") is the fad puzzle game that's sweeping the universe! Get with the program!
     The rules couldn't be simpler, and require no experience with higher mathematics beyond intermediate calculus. The Sudoku board is a grid of 81 cells in nine squares of 9 cells each (3 x 3). Just fill in the cells with the integers from 1 to 9 (only one number per cell, please!). Put any digit you like into each cell; the only stipulation is that the product of the nine numbers in any of the 3 x 3 blocks must be 362,880 (ditto with each row, horizontal and vertical as well as the two diagonals). You might be wondering about the significance of that big honkin' 6-digit number. It is 9! Dr. Petruso's
math-savvy readers out there will know that we don't shout out "Nine!" when we see this expression. No: it is 9 factorial, which means 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1. Anyway, that's all there is to it, kids!
      You newbies often find a calculator useful in deciding which number to write in each cell, but as your solving skills develop, you will be surprised at how quickly you are able to multiply incredibly humongous numbers in your head.
      Now get started by trying the Sudoku puzzle below, which is at the elementary level. Dr. Petruso has provided the first three numbers for you, to give you a big head start. (Hint: the product of 8 x 1 x 3 is 24, which you can verify on your calculator.) Just fill in the remaining cells right on your computer screen, using a black medium-point Sharpie™ marker.
      Average time to solution for this particular puzzle is 3 minutes. If it takes you more than 10 minutes, however, the international Sudoku Organization would give you a rating of "Moron." Good luck!


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