Dense Mondays |
arbor8 Kwon-Tom Obsessive Puzzles: 5584 Best Total: 13m 24s | Posted - 2012.07.16 15:44:27 Foilman confirmed recently that he has upgraded a bit the code used to generate the puzzles.One of the minor changes have been these two Friday Beasts.Another, Monday puzzles have had more givens. Counting June and July 2012, average number of givens is 53,7 (ranging from 48 to 60 ).I chose 2 random months ( Oct 2008 and Mar 2007 ) and the average was 48,5 (from 48 to 52). The number of givens was always divisible by 4. Is that a coincidence or a must-be fact? |
v_e_e_n_c_a Kwon-Tom Obsessive Puzzles: 2080 Best Total: 32m 53s | Posted - 2012.07.16 16:37:24
Quote: Originally Posted by arbor8 The number of givens was always divisible by 4. Is that a coincidence or a must-be fact?
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It is caused by the symmetry of puzzles plus the fact that the size of puzzle is even. For odd sizes this is not true. |
Jean Kwon-Tom Obsessive Puzzles: 2066 Best Total: 20m 50s | Posted - 2012.07.29 04:42:17 Actually, these even-sided puzzles will always have an even number of clues, but since they have rotational symmetry rather than reflectional, the number of clues doesn't have to be a multiple of 4. If you remove one clue, in order to keep the rotational symmetry, you would have to remove the one on the opposite side from the centre point at the same distance. Once you did that you wouldn't have to remove the mirror image ones, though, because not all of these puzzles have mirror symmmetry. |