Please explain "Elimination in inner-outie differences in Box..."
I don't understand/can't work this out. I'm doing the latest Assassin Killer and looking at Box 2
Thanks
Sumocue hints
Hi Nick,
here (I think) is the situation where you will first encounter an innie-outie difference in nonet 2:
The 2 green cells are the outies.
The red cell is the innie.
The sum of the 3 cages covering nonet 2 is 43, so the 2 green cells together must be 2 less than the single innie.
The minimum value for the 2 outies is 3 (1+2), so the innie must be at least 5. You can eliminate digits 1 through 4 in the innie.
The maximum value for the innie is 9, so the 2 outies together can be a maximum of 7. This means that neither of them can be higher than 6. You can eliminate candidates 7 through 9 from these 2 cells.
Hope this helps you understand the technique.
Ruud
here (I think) is the situation where you will first encounter an innie-outie difference in nonet 2:
The 2 green cells are the outies.
The red cell is the innie.
The sum of the 3 cages covering nonet 2 is 43, so the 2 green cells together must be 2 less than the single innie.
The minimum value for the 2 outies is 3 (1+2), so the innie must be at least 5. You can eliminate digits 1 through 4 in the innie.
The maximum value for the innie is 9, so the 2 outies together can be a maximum of 7. This means that neither of them can be higher than 6. You can eliminate candidates 7 through 9 from these 2 cells.
Hope this helps you understand the technique.
Ruud
“If the human brain were so simple that we could understand it, we would be so simple that we couldn't.” - Emerson M Pugh
Sumocue hints
Ruud - thanks for reply to my question on innie-outie differences on the latest Assassin Killer
I'm still trying to get my head round this and seem to have a mental blockage! Could you run through Nonet 3 and Nonet 7 innie-outie difference for me as well? With a couple more examples it may well click for me - I seem to react intuitivelyto these kind of problems if I have more examples
Many thanks
Nick
I'm still trying to get my head round this and seem to have a mental blockage! Could you run through Nonet 3 and Nonet 7 innie-outie difference for me as well? With a couple more examples it may well click for me - I seem to react intuitivelyto these kind of problems if I have more examples
Many thanks
Nick
Hi Nick
Here’s how I look at it.
Total for N3 = 45 = 27 + 18 - outies + innies.
=> 45 = 45 - r4c8 + r13c7 (in this case the 1 outie = the 2 innies)
From this you can make eliminations :
The min possible for any two cells (the innies) is 3 => the min for the outie also = 3
=> r4c8 <> 1 or 2 and you can eliminate them as candidates
Conversely, the max possible for any one cell (the outie) is 9 so you know that the max possible for the 2 innies is also 9.
-------------------------------------------------------------------------------------
Total for N7 = 45 = 22 + 24 - r6c1 (outie) + r7c23 (innies)
=> 45 = 46 - r6c1 + r7c23
=> r6c1 = 1 + r7c23 ( in this case the outie = the 2 innies +1)
The max for the outie = 9 => max for the innies = 8
=> r7c23 <> 8 or 9 and you can eliminate them as candidates
The min for the innies = 3 => min for the outie = 4
=> r6c1 <> 1 or 2 or 3 and you can eliminate them as candidates
Here’s how I look at it.
Total for N3 = 45 = 27 + 18 - outies + innies.
=> 45 = 45 - r4c8 + r13c7 (in this case the 1 outie = the 2 innies)
From this you can make eliminations :
The min possible for any two cells (the innies) is 3 => the min for the outie also = 3
=> r4c8 <> 1 or 2 and you can eliminate them as candidates
Conversely, the max possible for any one cell (the outie) is 9 so you know that the max possible for the 2 innies is also 9.
-------------------------------------------------------------------------------------
Total for N7 = 45 = 22 + 24 - r6c1 (outie) + r7c23 (innies)
=> 45 = 46 - r6c1 + r7c23
=> r6c1 = 1 + r7c23 ( in this case the outie = the 2 innies +1)
The max for the outie = 9 => max for the innies = 8
=> r7c23 <> 8 or 9 and you can eliminate them as candidates
The min for the innies = 3 => min for the outie = 4
=> r6c1 <> 1 or 2 or 3 and you can eliminate them as candidates
Sumocue hints
Ruud
Many thanks for your help - I think I am beginning to get the hang of it now. I love killers, having polished off the Times Killer Sudoku book, and finishing the Sudokulist Extreme Killer each week in fairly quick time. Strange how one gets a mental blockage sometimes!
Nick
Many thanks for your help - I think I am beginning to get the hang of it now. I love killers, having polished off the Times Killer Sudoku book, and finishing the Sudokulist Extreme Killer each week in fairly quick time. Strange how one gets a mental blockage sometimes!
Nick