The New Sudoku Players' Forum

[DonM]

xy-chain: r7c6-4-r7c7-1-r2c7-8-r2c1-5-r4c1-9-r4c6-4-r7c6 => r7c6<>4

sue de coq: 1245r7c89 + 12r7c6 + 45r8c9: r7c4<>12, r8c8r9c78<>45

This is one of the most frustrating puzzles I have ever encountered. There are many xy-chains and things that get close to eliminating something, but not quite. The total number of minutes and swear words used to get this far is about 30.

Oh, wait. Those eliminations don't do anything. (Sigh)

But they're very clever nonetheless!

[StrmCkr]

Code: Select all

*--------------------------------------------------------------------*
 | 7      128U    4      | 18U     5      189    | 6      3      129U    |
 | 58@     125U    9      | 36     4      36     | 18@     7      12U     |
 | 3      18U     6      | 189U    2      7      | 5      48@     49@     |
 |----------------------+----------------------+----------------------|
 | 59     6      2      | 7      8      49     | 3      145    145    |
 | 1      45     7      | 26     3      26     | 49     459    8      |
 | 89     48     3      | 49     1      5      | 2      6      7      |
 |----------------------+----------------------+----------------------|
 | 6      7      8      | 1245   9      124    | 14     1245   3      |
 | 24     9      1      | 23458  6      2348   | 7      2458   45     |
 | 24     3      5      | 1248   7      1248   | 1489   12489  6      |
 *--------------------------------------------------------------------*

Here yah go DonM

a very messed up move



A self contradicting double Aura (aka Permeable mug)


(1)R2C7 - (2)R2C9 – (9)R1c9 = (18)R1C46{hp) => R1C2<>18
|
(8)R2C7 – (5)R2C1 –(4)R3C8 –(9)R3C9 =(12)R12C9+(12)R12C3 {ur}
|
But wait there is also an overlapping UR on digits (18) (expressed by the same chain (ill draw it to show easier)

Code: Select all

128(R1C2)====18(R1C4)=======12(r1C9)
||           ||               ||
12(R2C2)=====||==============12(R2C9)
||           || 
18(R3C2======18 (r3C4)

=> basicaly the mug says R1C2 = both 2 and 8 to avoid both urs.
 
thus it cant happen

so

R2C7 <1>

there is more elliminations but its all a chain off of this cell.

Singles from here out

if anyone wants or can pls re write it so it looks proper.
the chian works off all the @ cells using hidden pairs to show that
r2c7 = 1 & never 8
etc...

solving time:
<1 min... time to show this ... >20 mins.
err wish i could post stuff clearly

fun puzzle there is lots of ways to solve this one... i like the aura though...

[udosuk]

This is my offering:

Code: Select all

+----------------------+----------------------+----------------------+
| 7      128    4      | 18     5      189    | 6      3      129    |
| 58     125    9      | 36     4     #36     | 18     7      12     |
| 3      18     6      | 189    2      7      | 5      48     49     |
+----------------------+----------------------+----------------------+
| 59     6      2      | 7      8      49     | 3      145    145    |
| 1      45     7      | 26     3     #26     | 49     459    8      |
| 89     48     3      | 49     1      5      | 2      6      7      |
+----------------------+----------------------+----------------------+
| 6      7      8      |-4125   9     *124    |*14     1245   3      |
| 24     9      1      | 23458  6     *2348   | 7      2458   45     |
| 24     3      5      |*1248   7     *1248   | 1489   12489  6      |
+----------------------+----------------------+----------------------+

r25c6 from {236}
=> r78c6 can't be [23]
=> r7c67+r8c6+r9c46 can't be [213{18}]
=> r7c4 can't be 4

After this the remaining should be much easier.

[Luke]

You know Don, this SAM idea of yours started out to be fun but now it's getting downright educational .

UR12[(9)r9c1 = (1)r3c2]...

I've recently learned how to use URs in chains, but I never looked at it quite like this. When you wrote "neither the 9 in r1c9 nor the 1 in r3c2 can both be false," that sounded familiar. Of course, it's the very definition of a strong link, "two premises cannot both be false." Since I like the URs, I'm sure I'll be incorporating more in my chains now that you've helped me put two and two together.

r25c6 from {236}
=> r78c6 can't be [23]
=> r7c67+r8c6+r9c46 can't be [213{18}]
=> r7c4 can't be 4

I always like to see these moves because they balance my chain obsession with an alternative perspective. I don't know how udosuk comes up with these, but when I've had success doing this, I've worked backward, like painting negative space. If [23] can't be in those two cells, place them there, note the left-over candidates, then work backwards from that simplified position. It can crystallize pretty quickly sometimes. I'd be interested in hearing the author's approach (or I can wait for the book.)

2. 24r9c14=18r19c4-

Never seen that done before!

What I'm not getting is the MUG.

There's a Type 2 uniqueness test on (236)MUG:r258c46 that implies r8c46<>2.

I've looked at the MUG thread but it's not sinking in. If anyone's up to explaining MUGs using this example I'd be grateful.

[StrmCkr]

http://forum.enjoysudoku.com/viewtopic.php?p=21050#p21050

is the mug thread.

that other one covers permable mugs (my example)

Code: Select all

12 | 123 13
12 | 12  .
------------
.  | 13  13

a mug is usually two unique rectangles overlapping in 1 cell. (R2C1)

12 12
12 12

or

13 13
13 13

with r2c2 being equal to 1,2,3

you get 3 solutions.

which is deadly.

to avoid such an aragment is what a mug does.

a permeable mug uses the muti Universal graves concepts and applies it to outside cells that directly expresses a mug pattern.

in this case the 4@ cells induce the mug pattern.
all cells that force the mug cannot occur.
elaborated better by udosuk. further down.

[DonM]

You know Don, this SAM idea of yours started out to be fun but now it's getting downright educational .

What I'm not getting is the MUG.

Glad you're enjoying the thread. btw: There are all sorts of Mugs:

A skeleton goes into a bar and says to the bartender: 'Give me a beer and a mug'. (Think about it guys before saying 'Huh?')

[DonM]

Code: Select all

*--------------------------------------------------------------------*
 | 7      128    4      | 18     5      189    | 6      3      129    |
 | 58     125    9      | 36     4      36     | 18     7      12     |
 | 3      18     6      | 189    2      7      | 5      48     49     |
 |----------------------+----------------------+----------------------|
 | 59     6      2      | 7      8      49     | 3      145    15     |
 | 1      45     7      | 26     3      26     | 49     459    8      |
 | 89     48     3      | 49     1      5      | 2      6      7      |
 |----------------------+----------------------+----------------------|
 | 6      7      8      | 1245   9      124    | 14     1245   3      |
 | 24     9      1      | 23458  6      2348   | 7      2458   45     |
 | 24     3      5      | 1248   7      1248   | 1489   12489  6      |
 *--------------------------------------------------------------------*

After the r4c9<>4 due to the W-wing (mentioned also by Luke), this is my main opening move for the puzzle at this point. It opens the grid up for the final moves by exposing a strong link on 1s in c7 and on 4s in box 9. The column-based almost jellyfish (jf) is not really necessary, but was used to avoid using a common cell (though as far as I can tell it would have been perfectly valid):

AIC: (8)r6c2=jf(8)c2468r1389-r9c7=grp(8)r78c8-(8=4)r3c8-r3c9=r8c9-(4=1)r7c4-r2c7=grp(1)r12c9-(1=5)r4c9-r4c1=(5-4)r5c2=(4)r6c2 - loop

NL: r6c2 =8= jf(8)c2468r1389 -8- r9c7 =8= r78c8 =4= r3c8 -4- r3c9 =4= r8c9 -4- r7c7 -1- r2c7 =1= r12c9 -1- r4c9 -5- r4c1 =5= r5c2 =4= r6c2

=> r4c8<>5, r9c7<>14, r789c8<>4 -> exposes 2-string kite(4)r57c7/r4c68: r7c6<>4

[ronk]

What I'm not getting is the MUG.

There's a Type 2 uniqueness test on (236)MUG:r258c46 that implies r8c46<>2.

I've looked at the MUG thread but it's not sinking in. If anyone's up to explaining MUGs using this example I'd be grateful.

Sorry, I should have called it a BUG-Lite. At least one of r8c46 must be a digit other than digits 2 and 3. Moreover, as in a UR Type 2, digit 3 only exists in the BUG-Lite cells of r8.

There is a useful relationship between a MUG and a BUG-Lite, but this is not an appropriate example with which to explain.

[udosuk]

This is my offering: ...

On 2nd thought the following presentation might be a bit more elegant:

Code: Select all

+----------------------+----------------------+----------------------+
| 7      128    4      | 18     5      189    | 6      3      129    |
| 58     125    9      | 36     4     *36     | 18     7      12     |
| 3      18     6      | 189    2      7      | 5      48     49     |
+----------------------+----------------------+----------------------+
| 59     6      2      | 7      8      49     | 3      145    145    |
| 1      45     7      | 26     3     *26     | 49     459    8      |
| 89     48     3      | 49     1      5      | 2      6      7      |
+----------------------+----------------------+----------------------+
| 6      7      8      |-4125   9     *124    |*14     1245   3      |
| 24     9      1      | 23458  6     #2348   | 7      2458   45     |
| 24     3      5      |#1248   7     #1248   | 1489   12489  6      |
+----------------------+----------------------+----------------------+

#: r8c6+r9c46 from {12348} must have at least one of {234}
=> *: r25c6+r7c467 can't be [36421]
=> r7c4 can't be 4



Also, this is an alternative presentation of StrmCkr's "MUG" move:

Code: Select all

+----------------------+----------------------+----------------------+
| 7    #@128    4      |@18     5      189    | 6      3     #129    |
|*58    #125    9      | 36     4      36     |-81     7     #12     |
| 3     @18     6      |@189    2      7      | 5     *48    *49     |
+----------------------+----------------------+----------------------+
| 59     6      2      | 7      8      49     | 3      145    145    |
| 1      45     7      | 26     3      26     | 49     459    8      |
| 89     48     3      | 49     1      5      | 2      6      7      |
+----------------------+----------------------+----------------------+
| 6      7      8      | 4125   9      124    | 14     1245   3      |
| 24     9      1      | 23458  6      2348   | 7      2458   45     |
| 24     3      5      | 1248   7      1248   | 1489   12489  6      |
+----------------------+----------------------+----------------------+

To avoid any of r12c29 (#) & r13c24 (@) to form a deadly pattern ({12} or {18}), at least one of the following three must be true:

r1c9=9 or r2c2=5 or r3c4=9

If r2c2=5, then r2c1=8
If r1c9=9 or r3c4=9, then r3c9=4 => r3c8=8

Therefore at least one of r2c1+r3c8 must be 8
=> r2c7, seeing r2c1+r3c8, can't be 8, must be 1.

Let's see if it's clearer to you, Luke.

[StrmCkr]

Code: Select all

A skeleton goes into a bar and says to the bartender: 'Give me a beer and a mug'. (Think about it guys before saying 'Huh?')

nice one

needs a face :P
any takers on rewording mine id like to see it displayed properly... or diffrently.

edit:
thanks udosuk

[udosuk]

A skeleton goes into a bar and says to the bartender: 'Give me a beer and a mug'. (Think about it guys before saying 'Huh?')

Sorry I'm not very good in understanding these jokes. No idea about StrmCkr's "needs a face" interpretation, but my own interpretation is like this: the skeleton has no bladder, so has to borrow the mug to put down between his feet so that the beer (after entering his "body") won't wet the floor.

Hope DonM can give the official elaboration later.

[StrmCkr]

another word for a persons face is "mug"

a skeleton deffintly doesnt have a face.

hope that helps.

[DonM]

another word for a persons face is "mug"

a skeleton deffintly doesnt have a face.

hope that helps.

strmckr has it. The skeleton can't drink liquid without a face ie. a mug. However, in all fairness to udosuk, the term 'mug' may be more well-known to Americans where in old movies they would talk about a guy having an 'ugly mug'. And then there is the still-used term, mug-shot, for the photo taken when one is arrested.

[udosuk]

strmckr has it.

Well, if you're the original creator of that joke, you can elaborate any way you like.

Just 3 points:

1. According to my knowledge, 75%+ of bar/beer/alcoholic jokes has something to do with urination or human excretory/reproductive systems/organs (e.g. "A skeleton goes into a bar and says to the bartender: 'Give me a beer and a mop'.").

2. As for "the skeleton can't drink liquid without a face", well a skeleton can't drink liquid without many things, but I'm not convinced that "a face" is one of them.

3. With the interpretation of you guys I have difficulty in finding much humour out of this joke. (So a skeleton asks the bartender to lend him "a mug", which is a pun to "a face", and then what? So he wears it and drinks the beer? What's so funny about that?)

Perhaps the real joke is on me, arguing on the lameness of a joke in here. So I'll just shut the bell up and go to a real pub to ask for a beer and a mug or a mop.

[Luke]

Gentlemen, gentlemen, please settle down. You're starting to treat Sudoku like it's some kind of a game.....