The New Sudoku Players' Forum

by **daj95376** » Tue Feb 06, 2007 8:03 am

wapati wrote:There is a Jelly, you cannot avoid, pattern wise.

Tough puzzle, for me. [Very tough, for me]

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

Code: Select all: # Singles # Sashimi Swordfish c357/r(23)57 # Singles *-----------------------------------------------------------* | 4 1 5 | 7 9 8 | 3 2 6 | | 9 3 7 | 5-4 2 6 |*45 8 1 | | 2 8 6 | 3 *45 1 | 9 457 457 | |-------------------+-------------------+-------------------| | 7 45 1 | 2 8 3 | 6 9 45 | | 58 6 *48 | 1 *457 9 |*457 3 2 | | 3 9 2 | 45 6 57 | 1 457 8 | |-------------------+-------------------+-------------------| | 58 2457 *48 | 6 3 257 |*457 1 9 | | 6 2457 3 | 9 1 257 | 8 457 457 | | 1 57 9 | 8 57 4 | 2 6 3 | *-----------------------------------------------------------*

by **wapati** » Tue Feb 06, 2007 9:27 am

Nice find Danny!

by **daj95376** » Tue Feb 06, 2007 8:13 pm

wapati wrote:Nice find Danny!

Thanks Jim! (Hah, got your name right this time!)

I wish that I could claim my solution involved *skill*. Instead, when I ran my solver with sd-DIC/Nets disabled, it returned a fat list of Template eliminations on <4> to solve the puzzle. I then knew it was only necessary to find a fish that would leave only one cell containing <4> in a unit. While scanning the bi-location units, the Sashimi Swordfish jumped out at me and scared me half to death.

by **wapati** » Fri Feb 09, 2007 7:54 am

daj95376 wrote:
wapati wrote:Nice find Danny!

Thanks Jim! (Hah, got your name right this time!)

Here is another nasty pattern puzzle!

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

Thanks Danny, you did nail my name!

by **wapati** » Fri Feb 09, 2007 8:04 am

Pretty tough cookie.

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

by **Carcul** » Fri Feb 09, 2007 12:39 pm

Wapati wrote:Pretty tough cookie.

Code: Select all: *------------------------------------------------------------* | 12356 29 159 | 8 35 7 | 146 125 145 | | 1356 35 7 | 1345 2 1456 | 16 9 8 | | 1256 4 8 | 15 9 156 | 3 1257 157 | |-------------------+--------------------+-------------------| | 9 57 15 | 2 578 1458 | 147 3 6 | | 157 6 3 | 14579 57 1459 | 2 8 145 | | 4 8 2 | 157 6 3 | 17 15 9 | |-------------------+--------------------+-------------------| | 2378 29 6 | 379 1 89 | 5 4 237 | | 237 1 59 | 37 4 59 | 8 6 237 | | 3578 357 4 | 6 3578 2 | 9 17 137 | *------------------------------------------------------------*

[r4c7]=1|4=[r5c6](-4-[r23c6|r5c9])=9=[r5c4]-9-[r78c4]-7-[r6c4]=
={ATILA}=7=[r3c9]-7-[r3c8]=7=[r9c8]=1=[r9c9]-1-[r5c9]=1=[r6c8]=5=
=[r6c4]=1=[r3c4]=5=[r23c6]-5-[r8c6]=5=[r8c3]=9=[r7c2]-{Unique Pattern}, => r4c7=1.

Carcul

by **Carcul** » Fri Feb 09, 2007 12:58 pm

Wapati wrote:Here is another nasty pattern puzzle!

Code: Select all: *----------------------------------------------------------------* | 179 4 8 | 39 6 179 | 5 2 139 | | 6 137 179 | 349 5 2 | 3478 1349 13489 | | 5 137 2 | 8 37 1479 | 347 1349 6 | |---------------------+--------------------+---------------------| | 1478 17 5 | 12 9 3 | 248 6 148 | | 3 9 14 | 12 48 6 | 248 7 5 | | 148 2 6 | 7 48 5 | 9 134 1348 | |---------------------+--------------------+---------------------| | 479 6 3479 | 5 37 8 | 1 349 2 | | 2 8 349 | 6 1 49 | 34 5 7 | | 1479 5 13479 | 349 2 479 | 6 8 349 | *----------------------------------------------------------------*

1. [r3c8]=9=[r3c6]-9-[r8c6]=9=[r8c3](-9-[r7c13]=9=[r7c8]-9-[r3c8])-9-
-[r2c3]=9=[r1c1]-9-[r1c9], => r1c6/r1c9/r9c6/r9c1/r9c3/r2c8<>9.

Then the XY-Wing solves the puzzle.

Carcul

by **Carcul** » Fri Feb 09, 2007 1:44 pm

Wapati wrote:Lots of methods, often more than once.

Code: Select all: *--------------------------------------------------------------* | 129 124 8 | 579 3 279 | 12469 2459 1269 | | 239 6 3459 | 589 29 1 | 7 2459 289 | | 7 12 159 | 589 6 4 | 129 3 1289 | |--------------------+--------------------+--------------------| | 8 127 179 | 4 5 79 | 3 6 129 | | 4 3 179 | 2 79 6 | 189 89 5 | | 29 5 6 | 1 8 3 | 249 2479 279 | |--------------------+--------------------+--------------------| | 13 9 13 | 6 27 5 | 28 278 4 | | 5 78 2 | 3 4 789 | 69 1 679 | | 6 478 47 | 79 1 2789 | 5 279 3 | *--------------------------------------------------------------*

1. [r123c4]-9-[r9c4]-7-[r7c5]-2-[r2c5]-9-[r123c4], => r123c4<>9.

2. [r5c7]=1=[r4c9]=2=[r4c2]-2-[r6c1]-9-[r1c1]=9|4=[r1c2]-4-[r9c2]
=4|2=[r9c6]-2-[r7c5]-7-[r5c5]=7=[r5c3]=1=[r5c7], => r5c7=1.

3. [r6c7]=4=[r6c8]=9=[r2c8]-9-[r3c7]-2-[r6c7], => r6c7<>2.

Carcul

by **Carcul** » Tue Feb 13, 2007 7:30 pm

Wapati wrote:This one needs an xy but has many other pattern potentials, big fish and small.

Code: Select all: *--------------------------------------------------------------* | 27 3 9 | 57 6 24 | 1257 578 12458 | | 1 5 67 | 8 24 9 | 67 3 24 | | 8 2467 2467 | 57 3 1 | 25679 5679 25 | |--------------------+-------------------+---------------------| | 2369 1 236 | 69 7 36 | 4 58 58 | | 4 8 367 | 2 1 5 | 367 67 9 | | 3679 67 5 | 469 8 346 | 1367 2 13 | |--------------------+-------------------+---------------------| | 256 246 1 | 3 245 8 | 259 59 7 | | 235 9 8 | 1 25 7 | 235 4 6 | | 2357 247 2347 | 46 9 246 | 8 1 235 | *--------------------------------------------------------------*

1. [r5c7]-3-[r6c79]=3,1|3=[r5c3]-3-[r5c7], => r5c7<>3.

2.[r2c5](-4-[r7c5])-4-[r2c9]-2-[r3c9](-5-[r9c9]-3-[r8c7])-5-[r3c7]-9-
-[r7c7], => r2c5<>4 solving the puzzle.

Carcul

by **Carcul** » Thu Feb 15, 2007 2:08 pm

Wapati wrote:Whew, what to say. Emm, lots of work, pattern wise. Fins, for true.

Code: Select all: *-----------------------------------------------------* | 4 1 5 | 2 89 6 | 3 7 89 | | 7 389 2 | 389 5 4 | 1 69 689 | | 389 6 389 | 1 7 389 | 5 4 2 | |-----------------+-----------------+-----------------| | 6 289 7 | 5 1 89 | 29 3 4 | | 2389 4 389 | 6 389 7 | 29 1 5 | | 1 5 39 | 39 4 2 | 6 8 7 | |-----------------+-----------------+-----------------| | 2389 7 1 | 389 26 389 | 4 5 69 | | 5 29 4 | 7 26 1 | 8 69 3 | | 389 389 6 | 4 389 5 | 7 2 1 | *-----------------------------------------------------*

At least one of {r3c1|r5c3|r7c1|r7c4|r9c5} must be "3". But:

[r7c6](-3-[r7c14|r9c5])-3-[r3c6]=3=[r2c4]-3-[r2c2]=3=[r9c2]-{ATILA:
[r3c3]-3-[r3c1]=3=[r5c3]-3-[r3c3]}-3-[r3c3]-{ATILA(89): r4c2|r2c2|
|r3c3|r3c6|r4c6}=2=[r4c2]-2-[r5c1]=2=[r7c1]-{TILA(9): r9c1|r9c5|r1c5|
|r3c6|r3c3|r2c2|r8c2}.

So, r7c6<>3. After that:

[r9c5]=3|2=[r4c2]-2-[r5c1]=2|3=[r5c3]-3-[r5c5]=3=[r9c5],

which implies r9c5=3 and the puzzle is solved.

Carcul

by **wapati** » Thu Feb 15, 2007 10:19 pm

Carcul wrote:
Wapati wrote:Whew, what to say. Emm, lots of work, pattern wise. Fins, for true.

Code: Select all
*-----------------------------------------------------* | 4 1 5 | 2 89 6 | 3 7 89 | | 7 389 2 | 389 5 4 | 1 69 689 | | 389 6 389 | 1 7 389 | 5 4 2 | |-----------------+-----------------+-----------------| | 6 289 7 | 5 1 89 | 29 3 4 | | 2389 4 389 | 6 389 7 | 29 1 5 | | 1 5 39 | 39 4 2 | 6 8 7 | |-----------------+-----------------+-----------------| | 2389 7 1 | 389 26 389 | 4 5 69 | | 5 29 4 | 7 26 1 | 8 69 3 | | 389 389 6 | 4 389 5 | 7 2 1 | *-----------------------------------------------------*

At least one of {r3c1|r5c3|r7c1|r7c4|r9c5} must be "3". But:

[r7c6](-3-[r7c14|r9c5])-3-[r3c6]=3=[r2c4]-3-[r2c2]=3=[r9c2]-{ATILA:
[r3c3]-3-[r3c1]=3=[r5c3]-3-[r3c3]}-3-[r3c3]-{ATILA(89): r4c2|r2c2|
|r3c3|r3c6|r4c6}=2=[r4c2]-2-[r5c1]=2=[r7c1]-{TILA(9): r9c1|r9c5|r1c5|
|r3c6|r3c3|r2c2|r8c2}.

So, r7c6<>3. After that:

[r9c5]=3|2=[r4c2]-2-[r5c1]=2|3=[r5c3]-3-[r5c5]=3=[r9c5],

which implies r9c5=3 and the puzzle is solved.

Carcul

Carcul, I don't read chains so I wish to ask, does the length of your post suggest that this was hard to solve? (It was quite involved for me.)

by **wapati** » Thu Feb 15, 2007 10:31 pm

I don't see an easy path for this one.

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

by **wapati** » Thu Feb 15, 2007 11:06 pm

This has a lot of hard patterns, used...not often

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

by **wapati** » Fri Feb 16, 2007 1:02 am

Prety nasty!

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

by **Carcul** » Fri Feb 16, 2007 11:15 am

Wapati wrote:I don't see an easy path for this one.

Code: Select all: *--------------------------------------------------------------------* | 3 4 9 | 5 678 1 | 678 2 78 | | 6 178 17 | 237 3478 2348 | 13478 9 5 | | 178 5 2 | 367 9 348 | 134678 13678 1378 | |----------------------+----------------------+----------------------| | 5 9 6 | 8 1 23 | 237 37 4 | | 17 2 8 | 4 37 6 | 9 5 13 | | 4 137 137 | 27 5 9 | 128 18 6 | |----------------------+----------------------+----------------------| | 9 1378 1347 | 136 2 348 | 5 13678 1378 | | 2 1378 1347 | 136 3468 5 | 13678 13678 9 | | 18 6 5 | 9 38 7 | 138 4 2 | *--------------------------------------------------------------------*

[r2c4]=7=[r3c789]-7-[r1c79]=7=[r1c5]=6=[r8c5]=4=[r7c6](-4-[r3c6]
=4=[r3c7])=8=[r9c5]=3=[r9c7]=1=[r9c1]-1-[r3c1]=1=[r2c23]-1-[r2c7],

and so r2c4 must be “7” which solves the puzzle.

Carcul

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