State of the Sudoku - 10/21
More puzzles
*Intermediate - 2'07" (D4, empty box 5 as expected) - flowed very smoothly
*Advanced - 5'44" (with guess); later on paper, 5'5" logically but with some memory of the starting steps. This is on the borderline of solvable on whiteboard without assistance for me (but is not as hard as others we've seen I guess). I missed a 7 note in box 9 which would have helped spot a triple in column 9 as I was, for uniqueness reasons, looking at 3 and 9 in that column already in relevant places. But I didn't get it all together on the board and pushed digits instead. There is an easier pair to be had in that column too, but I was not using the box 9 plus box 3 far away information right, even on paper. So, this puzzle is in a hole for me; just as with naked singles, some kinds of pairs I get and others I miss. With just one solid path through, but a lot of either/or notes, this is a puzzle right on the borderline where I still fail to guess early enough because I hold out for the easy observation and either get it or don't. Anyway, not a reassuring puzzle but I did it rather late after a long day at work so I'll claim I was just tired.
*Solved on ~4' by 4' whiteboard
*Intermediate - 2'07" (D4, empty box 5 as expected) - flowed very smoothly
*Advanced - 5'44" (with guess); later on paper, 5'5" logically but with some memory of the starting steps. This is on the borderline of solvable on whiteboard without assistance for me (but is not as hard as others we've seen I guess). I missed a 7 note in box 9 which would have helped spot a triple in column 9 as I was, for uniqueness reasons, looking at 3 and 9 in that column already in relevant places. But I didn't get it all together on the board and pushed digits instead. There is an easier pair to be had in that column too, but I was not using the box 9 plus box 3 far away information right, even on paper. So, this puzzle is in a hole for me; just as with naked singles, some kinds of pairs I get and others I miss. With just one solid path through, but a lot of either/or notes, this is a puzzle right on the borderline where I still fail to guess early enough because I hold out for the easy observation and either get it or don't. Anyway, not a reassuring puzzle but I did it rather late after a long day at work so I'll claim I was just tired.
*Solved on ~4' by 4' whiteboard