awesome, Unike, thank you! Yes, very clear to me now. Will enable me to solve more sudokus for sure.
(I only knew the type one UR)
Oh, here's another type of unique rectangle. I remember about four weeks ago on an Expert I was able to operate on both ends of a unique rectangle at once. But I thought it was a special case. No, there is a general case, type 3:
(3, ) (3,6)
(3,6) (3, )
Neither of the empty positions is a 6.
Here's another, type 4:
(3,6) (3, )
( ,6) (3,6)
The two empty positions cannot be 6 or 3.
i thought that is only true of ONE of the two empties.
we get them all the time where one of them IS a 3 or a 6. just the other one can't be.
in fact we get it today
you must have only got lucky if you operated on the assumption that neither could be 3 or 6.
Done with greens
Done, no green, two guesses, one unlucky, one lucky. I didn't encounter a unique rectangle of any kind.
Hurshy, I think you didn't understand my notation. Each (3,6) represents a pair. Each open position means other numbers. If either empty spot is filled in, making three like pairs on three corners... ... yeah, maybe you are right. I'm experiencing a violation of Hurshy One right now, so I can't think clearly. I guess I'd better be careful with type 3 and type 4 UR's.