## Why isn't this a finned swordfish?

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### Why isn't this a finned swordfish?

I was playing this puzzle:
Code: Select all
`.-----------------.--------------------.-------------.| 278    35  9    | 25     2578  4     | 23  16   16 || 12678  28  1278 | 126    3     12678 | 9   5    4  || 126    35  4    | 12569  2569  1256  | 23  8    7  |:-----------------+--------------------+-------------:| 9      6   12   | 8      4     12    | 7   3    5  || 128    28  5    | 7      26    3     | 4   16   9  || 4      7   3    | 156    56    9     | 8   2    16 |:-----------------+--------------------+-------------:| 5      1   278  | 249    2789  278   | 6   479  3  || 3      9   6    | 24     1     278   | 5   47   28 || 278    4   278  | 3      569   56    | 1   79   28 |'-----------------'--------------------'-------------'`

And thought that when looking at "1's", rows 3, 4 and 6 formed a finned swordfish with the fin being at r4c3, but if it were true, I could eliminate the "1" from r5c1 and that gives me an error. So why aren't these 3 rows a finned swordfish?
JeJ

Posts: 76
Joined: 06 January 2011

### Re: Why isn't this a finned swordfish?

Looking at just the pencil marks for 1, we have:
Code: Select all
`. . . | . . . | . 1 11 . 1 | 1 . 1 | . . .1 . . | 1 . 1 | . . .------+-------+------. . 1 | . . 1 | . . .1 . . | . . . | . 1 .. . . | 1 . . | . . 1------+-------+------. . . | . . . | . . .. . . | . . . | . . .. . . | . . . | . . .`
A finned swordfish, ignoring the fin cells, should have 1s in exactly three rows and three columns. But even ignoring R4C3, rows 3, 4, & 6 have 1s in four columns (1, 4, 6, & 9).

JasonLion
2017 Supporter

Posts: 640
Joined: 25 October 2007
Location: Silver Spring, MD, USA

### Re: Why isn't this a finned swordfish?

JeJ,

I see a finned X-Wing c36\r24 fin at r3c6 with the exclusion r2c4 <> 1. I don't see how you could build a valid cover set with your proposed r346 base sets unless you use something like a finned franken fish. The only thing I could come up with for the r2c4 <> 1 elimination was c3b5\r24c4, but that's still an X-Wing instead of swordfish variety and it doesn't include all of your proposed base sets. I think the 1r6c9 candidate is the show stopper here, but I'm not an expert fisherman by any stretch of the imagination, so perhaps someone else has a valid cover set with eliminations for the r346 base set.

Cheers,
Paul
PIsaacson

Posts: 249
Joined: 02 July 2008

### Re: Why isn't this a finned swordfish?

You two are right, I didn't see the "1" on c9
JeJ

Posts: 76
Joined: 06 January 2011

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