Don't forget that the quantum cell can be used as an ALS.... simplest would be an xy wing........
tarek
gsf wrote:does the solution to this grid include r3c8=7?
ronk wrote:gsf wrote:does the solution to this grid include r3c8=7?
The original posting has r3c8 as the trivalue 147 ... but the deduction r2c7<>4 is apparently still valid.
 UR+3C/2SL: both strong links share a node, have different labels and one link includes the bivalue cell => "a" can be removed from "abY"
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ababX
a 
b

abY abZ
ababX
a 
b

ab ab
 UR+3C/2SL: both strong links share a node, have different labels and one link includes the bivalue cell => "a" can be removed from "abY", and Y and Z makes a quantum cell.
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ababX
a 
b

abY abZ
ravel wrote:
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**
 56 26 462  1458 7 9  3 4612 1248 
 1 9 4627  45+8 3 48  45+278 4627 248 
 357 37 8  45+1 2 6  45+7 #147 9 

 4 2378 1  78 5 2378  289 239 6 
 368 5 9  468 1468 12348  248 234 7 
 3678 23678 2367  46789 4689 23478  1 5 2348 
++
 2 178 5  3 1489 1478  6 1479 14 
 36789 13678 367  2 14689 1478  479 13479 5 
 3679 4 367  679 169 5  279 8 123 
**
...since its going crazy anyway: what about the elimination rep'nA found in the grid MJ showed above? You have 2 strong links for the 5 and a "finned" strong link for the 4 to eliminate 4 in r2c7.
abXabZ
a /

/ a

/ 
abY abW
ab abX

b

bY abZ
Steve R wrote:Havard’s observation of earlier today about a quantum cell, now incorporated in UR+3C/2SL, seems to apply more generally. In particular a may be missing from the candidates of one cell:
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ab abX

b

bY abZ
Eliminations involving the candidates in the sets Y and Z may still be made from the bottom row.
Steve
Steve R wrote:In particular a may be missing from the candidates of one cell:
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ab abX

b

bY abZ
Eliminations involving the candidates in the sets Y and Z may still be made from the bottom row.
a b
b a
ababX
a 
b

abY abZ
465.27..1798.4126.2136....4342.6....6572.4.8.189..342652...6...93...26..876435912
UR+3X/2SL: r34c78 => r4c9<>5,r7c8<>7,r8c8<>7,r4c7<>7,r3c7=57,r3c8<>5
++++
 4 6 5  389 2 7  38 39 1 
 7 9 8  35 4 1  2 6 35 
 2 1 3  6 589 89  578 579 4 
++++
 3 4 2  189 6 89  157 *57 579
 6 5 7  2 19 4  13 8 39 
 1 8 9  57 57 3  4 2 6 
++++
 5 2 14  1789 1789 6  37 347 378 
 9 3 14  178 178 2  6 457 578 
 8 7 6  4 3 5  9 1 2 
++++
ronk wrote:I'm not so sure about that. With the 'a' gone from the abY cell  and not "freely inventible"  the outcome ...
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a b
b a
... is not an indication of a deadly pattern. And there is neither a Y nor a Z in that.
..a..b
......
..b..a
ab abX

b

bY abZ
RW wrote:
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..a..b
......
..b..a
is always invertible if none of the involved numbers were part of the initial clues. You could never obtain any row information for any of the involved numbers from the remaining grid.
a b
b a
b a
a b