Today's sum sudoku set features some odd series of numbers rather than the usual 1 to 6.
Sorry about that. When I started creating this puzzle I goofed up and redrew the grid. I copied down some of the clues from the screw-up copy instead of the final - try it now.
April 20, 2010 (10:10 am)
I've solved the first four grids, but I'm having trouble with the last one. I think I can prove it is impossible to solve as numbered. Each row our column must add up to zero (because -5, -3, -2, 2, 3, 5 add up to zero). That means that the fourth row must end with -5. Now I see no way to make -2 at the top of the sixth column except -5 and 3 which conflicts with the -5 already in the column now.
Please double-check... it's suspicious that the third row has an unchecked region, so I'm guessing it was a transcription error.
April 20, 2010 (9:34 am)