tag:blogger.com,1999:blog-15868947.post8669128764322614632..comments2023-10-29T06:41:23.910-07:00Comments on Halfway There: In the numbersZenohttp://www.blogger.com/profile/09058127284297728552noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-15868947.post-62041702665998053752009-12-01T15:32:56.319-08:002009-12-01T15:32:56.319-08:00On checking Suduko grids...
After filling each su...On checking Suduko grids...<br /><br />After filling each subgrid with digits 1 to 9, row and column totals are not enough to guarantee validity of the whole gird. Of course the necessary checks are still fairly simple.<br /><br />Interestingly there are (only) two ways to partition the numbers 1 to 9 into three sets of three such that each set totals 15, which this grid illustrates:<br /><br />6 7 2<br />1 5 9<br />8 3 4<br /><br />(read across and down). Now each 3x3 block of a Suduko grid can be filled with some variant of this (rotated, transposed, row-shuffled etc), and all rows and columns will always total 45 without any guarantee that the grid is valid (ie. that each row and column consists of exactly the digits 1 to 9 also). Of course there are also many other ways to have valid subgrids and totals without having a valid full grid.<br /><br />No doubt interesting and efficient algorithms exist that can generate valid Suduko grids.Joffanhttps://www.blogger.com/profile/18025437863119781181noreply@blogger.comtag:blogger.com,1999:blog-15868947.post-1331574137369985302009-09-22T15:48:05.256-07:002009-09-22T15:48:05.256-07:00I've see Sudoku done with letters and with sym...I've see Sudoku done with letters and with symbols...<br /><br />But yeah: it looks like math.The Ridger, FCDhttps://www.blogger.com/profile/01538111197270563075noreply@blogger.comtag:blogger.com,1999:blog-15868947.post-70104979299271114602009-09-21T19:18:28.948-07:002009-09-21T19:18:28.948-07:00I think there are two other things going on here:
...I think there are two other things going on here:<br /><br />First, Sudoku involves numbers rather than words. So people perceive it as requiring more intelligence. <br /><br />Second, the ID people have made it a fad in creationist circles to care about arguments that look mathy. This letter fits that general trend.Joshuahttps://www.blogger.com/profile/00637936588223855248noreply@blogger.com