The New Sudoku Players' Forum

by **wapati** » Wed Jun 06, 2007 10:22 pm

This is a new thread of my same old.
The previous thread was disturbed and a new thread is warranted, to keep the pages easy to access.

Code: Select all: . . .|. 3 .|. . 9 . 9 2|8 . 6|. . . . 3 .|. . 4|6 2 . -----+-----+----- . . .|. . 9|. . 3 . 2 .|3 . 5|. 4 . 5 . .|7 . .|. . . -----+-----+----- . 8 4|6 . .|. 3 . . . .|9 . 2|4 8 . 2 . .|. 8 .|. . .

by **wapati** » Wed Jun 06, 2007 10:32 pm

Bonus puzzle.

Code: Select all: . 6 5|1 . .|. . . 4 . .|. 6 5|7 . . . . .|. 9 .|1 . . -----+-----+----- 8 . .|7 . .|. . 2 . . 6|. . .|4 . . 9 . .|. . 1|. . 3 -----+-----+----- . . 3|. 2 .|. . . . . 8|5 1 .|. . 9 . . .|. . 4|8 1 .

by **re'born** » Wed Jun 06, 2007 11:18 pm

here,wapati wrote:I see big fish, SE sees minnows.

Somewhere in between, I suspect!

Code: Select all
. . .|. 1 .|8 . 4 7 . 4|. . 2|. . . . 5 .|. 3 .|2 . . -----+-----+----- 6 3 .|. . 5|. . . . 4 5|2 . 8|3 6 . . . .|3 . .|. 5 8 -----+-----+----- . . 3|. 2 .|. 8 . . . .|7 . .|4 . 3 4 . 7|. 5 .|. . .

I see a remote naked pair, an xyz-wing and a 2-string kite. But with all of the potential deadly patterns out there, musn't there be a faster way to solve the puzzle?

by **wapati** » Thu Jun 07, 2007 12:10 am

Busy puzzle. SE uses APE, which I don't know.

Is APE a pattern?

Anyways, solvable by patterns that I know.

Code: Select all: 8 . .|2 . .|. . 9 . 7 .|. 6 .|. . 2 . 3 .|. . .|6 7 . -----+-----+----- . . .|6 . .|. 9 . . . 9|4 . 7|3 . . . 1 .|. . 5|. . . -----+-----+----- . 4 8|. . .|. 1 . 7 . .|. 8 .|. 2 . 6 . .|. . 3|. . 7

by **wapati** » Thu Jun 07, 2007 9:11 pm

Minnows, quite a few.

Code: Select all: . 9 8|. 7 1|. . . 3 7 .|2 . 6|. 9 . . . .|. . .|. . . -----+-----+----- . . 6|. 1 .|. 4 5 . . .|6 . 3|. . . 2 4 .|. 8 .|9 . . -----+-----+----- . . .|. . .|. . . . 5 .|1 . 9|. 6 7 . . .|7 2 .|1 5 .

by **wapati** » Thu Jun 07, 2007 9:15 pm

re'born wrote:
I see a remote naked pair, an xyz-wing and a 2-string kite. But with all of the potential deadly patterns out there, musn't there be a faster way to solve the puzzle?

LOL, good job, I had 4 as my shortest method. You want less than 3?
Ask Tarek or some other chain genius.

by **re'born** » Thu Jun 07, 2007 10:47 pm

wapati wrote:Busy puzzle. SE uses APE, which I don't know.

Is APE a pattern?

You can read about it here. It is a pattern, just not one I would recommend people spend much time looking for. In this case, I think the application of it is ridiculous when the much easier to spot skyscraper is around to make the same deductions. Inexplicably, the skyscraper is a higher rated pattern (in SE) than an APE which I think is complete nonsense.

by **wapati** » Thu Jun 07, 2007 11:09 pm

Thanks nrob'er!

I'll skip worrying about APE.

by **re'born** » Thu Jun 07, 2007 11:23 pm

wapati wrote:Minnows, quite a few.

Code: Select all
. 9 8|. 7 1|. . . 3 7 .|2 . 6|. 9 . . . .|. . .|. . . -----+-----+----- . . 6|. 1 .|. 4 5 . . .|6 . 3|. . . 2 4 .|. 8 .|9 . . -----+-----+----- . . .|. . .|. . . . 5 .|1 . 9|. 6 7 . . .|7 2 .|1 5 .

Basic techniques get you here:

Code: Select all: *-----------------------------------------------------------* | 56 9 8 | 34 7 1 | 56 23 234 | | 3 7 14 | 2 5 6 | 48 9 148 | | 1456 126 1245 | 348 9 48 | 56 7 134 | |-------------------+-------------------+-------------------| | 7 38 6 | 9 1 2 | 38 4 5 | | 59 18 59 | 6 4 3 | 7 128 28 | | 2 4 13 | 5 8 7 | 9 13 6 | |-------------------+-------------------+-------------------| | 1489 123 7 | 48 6 5 | 2348 38 3489 | | 48 5 24 | 1 3 9 | 248 6 7 | | 4689 36 349 | 7 2 48 | 1 5 3489 | *-----------------------------------------------------------*

To avoid a deadly pattern in r13c17<56>, we must have r3c1<>5,6. Moreover, there is a short xy-chain:

3-[r4c7]-8-[r2c7]-4-[r2c3]-1-[r6c3]-3, => r4c2<>3.

These two moves solve the puzzle.

by **daj95376** » Fri Jun 08, 2007 2:17 am

wapati wrote:Minnows, quite a few.

Code: Select all
. 9 8|. 7 1|. . . 3 7 .|2 . 6|. 9 . . . .|. . .|. . . -----+-----+----- . . 6|. 1 .|. 4 5 . . .|6 . 3|. . . 2 4 .|. 8 .|9 . . -----+-----+----- . . .|. . .|. . . . 5 .|1 . 9|. 6 7 . . .|7 2 .|1 5 .

One finned X-Wing is all that I find. Maybe it can be combined with the Empty Rectangle.

Code: Select all: b4 - 138 Naked Triple r1 - 234 Naked Triple r3 b1 - 2 Locked Candidate 1 r3 b2 - 8 Locked Candidate 1 c2b4 - 8 Locked Candidate 1 c7 - 2348 Naked Quad c9b3 - 1 Locked Candidate 1 c7b9 - 2 Locked Candidate 2 r1c8 <> 3 XY-Wing [r7c4]+[r1c4],[r7c8] c9b3 - 3 Locked Candidate 1 r7 b9 - 3 Locked Candidate 1 r3c2 <> 1 XY-Wing [r8c3]+[r2c3],[r7c2] r3c1 <> 56 UR Type 1 b1 - 14 Naked Pair c61 - 4 finned X-Wing r9c9 <> 4 Empty Rectangle r7c7 <> 8 XYZ-Wing [r7c9]+[r7c4],[r9c9] r7c8 <> 8 XYZ-Wing [r7c9]+[r7c4],[r9c9]

by **wapati** » Fri Jun 08, 2007 8:49 pm

Code: Select all: . . . | . 2 4 | . 9 . . . 6 | 8 . . | 3 . . . 7 . | . . . | . . . --------------------- . . . | . 3 9 | 8 . . . 9 4 | 5 . 8 | 1 2 . . . 8 | 4 1 . | . . . --------------------- . . . | . . . | . 6 . . . 5 | . . 3 | 4 . . . 6 . | 7 5 . | . . .

Swordfish, and several smaller...

by **wapati** » Fri Jun 08, 2007 8:51 pm

Think fins, SE thinks they are chains. (swords, maybe a jelly?)

Code: Select all: 6 . .|. . .|. . 4 9 8 .|. 2 .|. 1 5 . . .|8 . 6|. . . -----+-----+----- . . .|3 . 7|. . . 2 5 .|. 9 .|. 6 8 . . .|2 . 8|. . . -----+-----+----- 5 3 .|. . .|. 4 2 . . 6|. . .|9 . . . 7 .|. . .|. 8 .

by **wapati** » Sat Jun 09, 2007 8:57 pm

SQ sees swordfish, one each of the sashimi and finned types.
SE sees chains.

I see lots of small stuff and the swords also.

Code: Select all: 3 . . | . . . | . . 1 . 9 . | 4 . 1 | . 6 . . 1 4 | . . . | 8 9 . --------------------- . . 3 | . . . | 4 . . . 5 8 | 9 . 4 | 3 7 . 7 . . | . 3 . | . . 8 --------------------- 4 8 . | 6 . 5 | . 3 7 . 7 . | 8 . 3 | . 2 . . . . | . 7 . | . . .

by **wapati** » Sun Jun 10, 2007 2:41 pm

There is a robust Jellyfish in this puzzle, as well as many smaller patterns.

Code: Select all: . . 3 | . . . | . . 1 . 9 4 | . . . | . . . . 7 . | 2 . 4 | 9 3 . --------------------- . . . | . 3 . | 8 . 7 . 2 . | 4 . 8 | . 9 . 3 . 6 | . 9 . | . . . --------------------- . 4 2 | 3 . 7 | . 8 . . . . | . . . | 5 7 . 7 . . | . . . | 4 . .

by **daj95376** » Sun Jun 10, 2007 3:56 pm

wapati wrote:There is a robust Jellyfish in this puzzle, as well as many smaller patterns.

Code: Select all: # after: SSTS, Jellyfish, and XYZ-Wing # guardian cells (#) prevent invalid pattern r235\c15 (*) # => [r2c1]<>1 and [r3c5]<>1 # # also: Sashimi X-Wing c76\r67 => [r7c5]<>1 *-----------------------------------* | . . . | . . . | . . 1 | | *1- . . | #1 *1 . | . . . | | *1 . #1 | . *1- . | . . . | |-----------+-----------+-----------| | . 1 . | 1 . . | . 1 . | | *1 . . | . *1 . | . . . | | . . . | . . @1 | @1 1 . | |-----------+-----------+-----------| | 1 . . | . 1- . | @1 . . | | . . 1 | 1 . @1 | . . . | | . 1 1 | 1 . @1 | . 1 . | *-----------------------------------*

The first pattern is two overlapping finned X-Wings where one of the fin cells must be true.

The New Sudoku Players' Forum

Difficult Puzzles. Chains can be avoided.

Difficult Puzzles. Chains can be avoided.