Knight Tour Latin Square Problem Copyright 11-14-2005, Dan Thomasson Solution www.borderschess.org/KnightTour.htm Knight Tour Latin Square Tessellation In the Knight Tour Latin Square shown above, only one instance of each integer from 1 to 8 are in each row and column. The previous four 16-move mini-knight tours were combined to make the Latin Square. The knight moves for each tour are numbered from 1 to 8, then 1 to 8 is repeated a second time to complete the tour. After filling in the four tours shown above with the same color as their line color, they can be combined into one piece that can be tessellated. Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm There are all sorts of fun math oddities that can be found within this Knight Tour Latin Square. Notice in the diagram below on the left that each alternating horizontal number pair adds up to 9. Also, if you take the alternating horizontal number pairs as one number each (i.e. 2 and 7 as 27), they are multiples of 9 (i.e. 27 is 9x3). Alternating groups of 4 numbers each are shown in the above Latin Square on the right. Consider each group of 4 numbers as one number (i.e. 2, 7, 8, 1 as 2781). Divide 2781 by 9 to get 309. Do the same thing to all the 4-digit numbers on the left half of the square. Add up these 8 numbers to get 4444. Now do the same thing to the right half of the square. Notice that they also add up to 4444. 2781 / 9 = 309 1836 / 9 = 204 8163 / 9 = 907 7218 / 9 = 802 4527 / 9 = 503 3654 / 9 = 406 6345 / 9 = 705 5472 / 9 = 608 4444 4563 / 9 = 507 7254 / 9 = 806 2745 / 9 = 305 5436 / 9 = 604 6381 / 9 = 709 1872 / 9 = 208 8127 / 9 = 903 3618 / 9 = 402 4444 When all the numbers are divided by 9, the results are 3-digit numbers with a zero in the middle. Also, the digits on either side of the zero for the first eight 3-digit Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm results on the left side of the board, contain each of the digits from 2-9. The same occurs for the 3-digit results on the right side of the board. I found it interesting that 4444 is also the exact number of solutions to the excellent "Calmplex puzzle" designed by Andrew Snowie in Canada. Look at the results when doing the same dividing/adding process for each entire row: 27814563 / 9 = 3090507 18367254 / 9 = 2040806 81632745 / 9 = 9070305 72185436 / 9 = 8020604 45276381 / 9 = 5030709 36541872 / 9 = 4060208 63458127 / 9 = 7050903 54723618 / 9 = 6080402 44444444 Let's see how we can make a new 8x8 Magic Latin Square from the previous eight 8-digit results. All the rows, columns, and main diagonals should each add up to 44. 1. Remove all the zeros in each number to get the following eight 4-digit numbers. 3957 2486 9735 8264 5379 4628 7593 6842 2. Place these eight 4-digit numbers down the left side of an 8x8 grid square as shown in the square below. Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm 3. Reverse the order (vertically flip) of the eight 4-digit numbers and place them down the right side of the same square as shown above. 4. Add up all the rows, columns, and main diagonals to get 44 for each one. 5. Subtract "1" from all the digits inside the square to get a new Magic Constant of 36. Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm With the new 8x8 Magic Latin Square, we can make an 8x8x8 Magic Latin Cube where even the main diagonals of all faces of the cube, and the major internal diagonals equals 44. Also, all rows, columns, and pillars equal 44. Look at the eight levels. One row is rotated up each time to create a new level. Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm There are several number groups based on the number 9, or multiples of 9, that can be found in the original Knight Tour Latin Square. Here are a couple groups. See what other groups you can find. Groups Containing all digits from 1-8 Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm Groups Containing 4 digits adding up to 18 Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm Here is another Latin Cube I designed that is based on a Magic Square originating from 3-d Knight Moves: KTMS.htm. All rows, columns, main diagonals, and pillars each add up to 260. Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm Copyright 11-14-2005, Dan Thomasson www.borderschess.org/KnightTour.htm