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[ArkieTech]

Code: Select all

 *-----------*
 |..6|2..|...|
 |5.3|8..|.9.|
 |...|...|4..|
 |---+---+---|
 |3..|.2.|.1.|
 |.1.|...|.3.|
 |.9.|.6.|..8|
 |---+---+---|
 |..9|...|...|
 |.4.|..6|7.5|
 |...|..7|9..|
 *-----------*


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[Leren]

HUR 49 r45c49 => -9r5c4, XY Chain 1-r1c5-9-r8c5-3-r3c5-5-r3c6-3-r6c6-1 => -1r1c6.

[ArkieTech]

Code: Select all

 *--------------------------------------------------*
 | 4    7    6    | 2   c19   19   | 8    5    3    |
 | 5    2    3    | 8    7    4    | 1    9    6    |
 | 9    8    1    | 6    35   35   | 4    2    7    |
 |----------------+----------------+----------------|
 | 3    5    78   | 479  2    89   | 6    1    49   |
 | 6    1    78   | 479  459  589  | 2    3    49   |
 | 2    9    4    |a13   6    13   | 5    7    8    |
 |----------------+----------------+----------------|
 | 7    6    9    | 5    8    2    | 3    4    1    |
 | 1    4    2    | 9-3 c39   6    | 7    8    5    |
 | 8    3    5    |b14  c14   7    | 9    6    2    |
 *--------------------------------------------------*
als xy-wing
(3=1)r6c4-(1=4)r9c4-(1r9c5=3r8c5)r189c5 => -3r8c4; stte


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[tlanglet]

I usually get into trouble with moves like this but I continue to try.
Almost MUG(4789)r45c3469 External SIS 4r5c5 & 9r5c5 => -5r5c5

Or an AUR(49)r45c49 External SIS 4r5c5 & 9r5c5 => -5r5c5 works

[Edited to correct deletion as noted by Dan below]

[ArkieTech]

I usually get into trouble with moves like this but I continue to try.
Almost MUG(4789)r45c3469 External SIS 4r5c5 & 9r5c5 => 5r5c5

Or an AUR(49)r45c49 External SIS 4r5c5 & 9r5c5 => 5r5c5 works

Shouldn't it be -5r5c5 to break the dp

Very nice

[tlanglet]

Dan,

I am looking at the external inferences to prevent the DP. That is, at least one occurrence of digit 4, 7, 8 or 9
that shares a house with the potential DP must be true. The external digits that I used were 4r5c5 and 9r5c5; no external digits for 7 & 8 exist. If r5c5 must be a 4 or a 9, it will never equal 5.

[ArkieTech]

I am looking at the external inferences to prevent the DP. That is, at least one occurrence of digit 4, 7, 8 or 9
that shares a house with the potential DP must be true. The external digits that I used were 4r5c5 and 9r5c5; no external digits for 7 & 8 exist. If r5c5 must be a 4 or a 9, it will never equal 5.

[(4=9)r5c5]dp:r45c3469 => -5r5c5; stte

[tlanglet]

I am going to change my method of stating "not equal to" from "-" to "<>" . The "-" character is so small with the font used on this site that it is hard to see. I glanced at my original post based on the input by Dan and thought it included the "-", but I just now realized it was missing.

Sorry all for my blurry eyes that missed read my own post.

[Marty R.]

My rather inelegant solution is r5c5<>4. A 4 in that cell leads to an invalidity when doing an external analysis.

[eleven]

Almost MUG(4789)r45c3469 External SIS 4r5c5 & 9r5c5 => -5r5c5

Or an AUR(49)r45c49 External SIS 4r5c5 & 9r5c5 => -5r5c5 works

I agree with the first move, it's a nice DP and r5c6 must be 5 (or externally r5c5 must be 4 or 9)

Code: Select all

 |----------------+----------------+----------------|
 | 3    5   #78   |#479  2   #89   | 6    1   #49   |
 | 6    1   #78   |#479  459 #89+5 | 2    3   #49   |
 | 2    9    4    | 13   6    13   | 5    7    8    |
 |----------------+----------------+----------------|

But not the second, from the 49 DP also r56c6 could be 9.

[tlanglet]

Almost MUG(4789)r45c3469 External SIS 4r5c5 & 9r5c5 => -5r5c5

Or an AUR(49)r45c49 External SIS 4r5c5 & 9r5c5 => -5r5c5 works

I agree with the first move, it's a nice DP and r5c6 must be 5 (or externally r5c5 must be 4 or 9)

Code: Select all

 |----------------+----------------+----------------|
 | 3    5   #78   |#479  2   #89   | 6    1   #49   |
 | 6    1   #78   |#479  459 #89+5 | 2    3   #49   |
 | 2    9    4    | 13   6    13   | 5    7    8    |
 |----------------+----------------+----------------|

But not the second, from the 49 DP also r56c6 could be 9.

Eleven, Thanks for pointing out my mistake. I was more concern/interested in the MUG and, after the fact, included the AUR(49) remembering that the external inferences for the MUG but forgetting the 9s in r45c6. Here is my first on this forum, with many more to come.