## Finned Swordfish Plus Quasi-Empty Rectangle Pattern

Everything about Sudoku that doesn't fit in one of the other sections

### Finned Swordfish Plus Quasi-Empty Rectangle Pattern

There's probably a franken/mutant fish that'll perform this elimination. But I found something interesting, so I decided to share it -- a finned Swordfish in conjunction with a quasi-Empty Rectangle pattern.

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`.2...1...3...7..2...823...9..9..8..4.8.....6.4..9..3..8...974...6..1...8...6...7. #E026 5`

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`quasi-ER pattern through [b6](5) [r4c5]=[r4c78]-[r56c9]=[r12c9]`

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`finned Swordfish c167\r389 *-----------------------------------------------------------* | 9     2     567   | 458   56    1     |#5678  345   357   | | 3     145   156   | 458   7     9     |#1568  2     15    | |*15    1457  8     | 2     3    *456   |*1567  4-5   9     | |-------------------+-------------------+-------------------| | 6     3     9     | 17   !25    8     |@1257  15    4     | | 2     8     157   | 17    4     3     | 9     6     157   | | 4     157   157   | 9     256  @56    | 3     8     1257  | |-------------------+-------------------+-------------------| | 8     15    2     | 35    9     7     | 4     135   6     | | 7     6     34    | 345   1    *245   |*25    9     8     | |*15    9     34    | 6     8    *245   |*125   7     123   | *-----------------------------------------------------------*However, the finned Swordfish has two exo/remote cells -- [r4c7] and [r6c6].`

Here's where the combination effect comes into play. If [r4c5]<>5, then the quasi-ER pattern results in [r12c9]=5 and the elimination. If [r4c5]=5, then the exo/remote cells are cleared and the finned Swordfish performs the elimination.

Yes, setting either exo/remote cell to <5> will result in [r12c9]=5, but where's the fun in that.
daj95376
2014 Supporter

Posts: 2624
Joined: 15 May 2006

I don't understand your Quasi-ER but if it is true what about the extra 5 in r3c2 for your sword?
wapati
2010 Supporter

Posts: 527
Joined: 13 September 2006

wapati wrote:I don't understand your Quasi-ER but if it is true what about the extra 5 in r3c2 for your sword?

Eliminations occur only where there's an overlap between the finned Swordfish and the quasi-ER. Neither the finned Swordfish nor the quasi-ER can eliminate <5> in [r3c2] because they are both restricted to [b3].
daj95376
2014 Supporter

Posts: 2624
Joined: 15 May 2006

OK, I think I get it now, thanks.
wapati
2010 Supporter

Posts: 527
Joined: 13 September 2006