In thonky are described Naked and Hidden sets for n=2,3,4; in planetsudoku is for n=5;

theoretically n can be for 1 to 8, but n>4 are useless like N-fish degree > 4?

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In thonky are described Naked and Hidden sets for n=2,3,4; in planetsudoku is for n=5;

theoretically n can be for 1 to 8, but n>4 are useless like N-fish degree > 4?

theoretically n can be for 1 to 8, but n>4 are useless like N-fish degree > 4?

- Borneq
**Posts:**4**Joined:**25 July 2015

- Code: Select all
`3469 6789 347 | 4789 4579 1 | 368 35689 2`

169 2 17 | 789 3 578 | 4 5689 15689

1349 189 5 | 6 2 48 | 138 7 189

------------------------+----------------------+---------------------

12459 159 6 | 124789 4579 24578 | 78 58 3

459 3 8 | 479 45679 4567 | 2 1 4567

7 15 124 | 12348 456 234568 | 9 568 4568

------------------------+----------------------+---------------------

1236 4 1237 | 237 8 9 | 5 236 167

2356 567 9 | 237 1 2367 | 3678 4 678

8 167 1237 | 5 467 23467 | 1367 2369 1679

.....1..2.2..3.4....562..7...6.....3.38...21.7.....9...4..895....9.1..4.8..5.....

These higher level sets can be occasionally very useful. Consider above (Champagne, pattern game 0161) There is the naked quin of 45679 at r4c5, r5c456, r6c5, and the complementary hidden quads of 1238 at r46c46 (=> -479 r4c4, -457 r4c6, -4 r6c4 and -456 r6c6) .

Phil

- pjb
- 2014 Supporter
**Posts:**1723**Joined:**11 September 2011**Location:**Sydney, Australia

This complementarity is always or only in this case? For example http://planetsudoku.com/how-to/sudoku-naked-quint.html has no complementary hidden quad? But in the opposite direction: hidden sets are stronger and each naked set has complementary hidden set?

- Borneq
**Posts:**4**Joined:**25 July 2015

Borneq wrote:This complementarity is always or only in this case?

Always, it's just a different way of looking at the same thing. If you have a naked set, you can eliminate these digits from the other/complementary - not resolved - cells of this unit. This means, that you have a hidden set with the complementary digits there. Vice versa: if you have a hidden set, these digits cannot be in the complementary cells, thus there is a naked set of the other (not resolved) digits.

For example http://planetsudoku.com/how-to/sudoku-naked-quint.html has no complementary hidden quad?

Since two cells in the box are resoved, the complementary set is the hidden pair 23 (theoretically you also can call 2379 a hidden quad). The 23 pair is easy to spot, if you look at row 6 and column 8, which both have 2 and 3 outside the box 6.

- eleven
**Posts:**1582**Joined:**10 February 2008

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