Post the puzzle or solving technique that's causing you trouble and someone will help

Ok, I'm stuck. Why are the blues excluded here?

*-----------------------------------------------------------*
| 3 4 29 | 6 58 7 | 158 15 29 |
| 1 79 5 | 2 4 89 | 78 3 6 |
| 8 2679 269 | 15 3 19 | 57 4 29 |
|-------------------+-------------------+-------------------|
| 2 36 346 | 8 1 5 | 46 9 7 |
| 9 1 46 | 7 2 3 | 46 8 5 |
| 5 8 7 | 9 6 4 | 12 12 3 |
|-------------------+-------------------+-------------------|
| 7 35 13 | 4 9 12 | 25 6 8 |
| 6 59 189 | 15 7 128 | 3 25 4 |
| 4 25 28 | 3 58 6 | 9 7 1 |
*-----------------------------------------------------------*
JEAGoodman

Posts: 8
Joined: 13 March 2006

### Re: New Colors Help Please

JEAGoodman wrote:Why are the blues excluded here?

Because either pink or amber will ultimately be true, and at least one blue "sees" a pink and at least one blue sees an amber.

Ron
ronk
2012 Supporter

Posts: 4764
Joined: 02 November 2005
Location: Southeastern USA

I think I get it. You don't happen to have another puzzle with a two color solution like that for me to try to get on my own, do you?

Thanks so much!

Jeanne
JEAGoodman

Posts: 8
Joined: 13 March 2006

One of angusj’s – colour the 5s

Code: Select all
` *-----------------------------------------------------------* | 5     16    7     | 2     9     16    | 3     4     8     | | 2     168   3     | 4     578   168   | 156   17    9     | | 4     168   9     | 15    578   3     | 1256  127   57    | |-------------------+-------------------+-------------------| | 1     5     6     | 7     2     4     | 8     9     3     | | 9     7     2     | 8     3     5     | 4     6     1     | | 8     3     4     | 19    6     19    | 7     5     2     | |-------------------+-------------------+-------------------| | 3     2     15    | 6     4     89    | 159   178   57    | | 7     4     15    | 359   58    289   | 1259  1238  6     | | 6     9     8     | 35    1     7     | 25    23    4     | *-----------------------------------------------------------*`

and another – colour the 3s

Code: Select all
` *--------------------------------------------------* | 9    56   13   | 45   47   37   | 8    2    16   | | 7    2    4    | 1    6    8    | 9    3    5    | | 13   56   8    | 9    35   2    | 7    4    16   | |----------------+----------------+----------------| | 123  4    6    | 8    23   9    | 13   5    7    | | 8    9    135  | 45   47   37   | 13   6    2    | | 23   7    35   | 6    235  1    | 4    9    8    | |----------------+----------------+----------------| | 5    8    7    | 3    9    6    | 2    1    4    | | 6    3    2    | 7    1    4    | 5    8    9    | | 4    1    9    | 2    8    5    | 6    7    3    | *--------------------------------------------------*`

and one shamelessly stolen from Jeff - colour the 7s.

Code: Select all
`+----------------+----------------+----------------+ | 6    47   3    | 5    1    47   | 2    8    9    | | 8    257  27   | 6    9    3    | 4    57   1    | | 457  1    9    | 28   27   478  | 6    3    57   | +----------------+----------------+----------------+ | 1    8    6    | 9    3    5    | 7    2    4    | | 47   247  5    | 28   6    78   | 1    9    3    | | 9    3    27   | 4    27   1    | 5    6    8    | +----------------+----------------+----------------+ | 25   9    8    | 7    4    6    | 3    1    25   | | 3    57   4    | 1    8    2    | 9    57   6    | | 27   6    1    | 3    5    9    | 8    4    27   | +----------------+----------------+----------------+`
emm

Posts: 987
Joined: 02 July 2005

Thanks for your help Em, but I'm still not there. Let's take the 3s example you gave. I don't understand why r4c5 and r5c3 weren't eliminated but r4c1 was!
JEAGoodman

Posts: 8
Joined: 13 March 2006

JEAGoodman wrote:I don't understand why r4c5 and r5c3 weren't eliminated but r4c1 was!

Maybe you haven't yet seen these write-ups by Angus Johnson.Ron
ronk
2012 Supporter

Posts: 4764
Joined: 02 November 2005
Location: Southeastern USA

OK, JEAGoodman, I see where you’re coming from - it’s not enough to intersect just any old Aa with any old Bb ie r4c5 and r5c3.

First, one from each colour must also share a group = A and B in r5
therefore one or both of their conjugates must be true
therefore any cell that intersects both their conjugates must be false.

Code: Select all
` .   . 3A| .  .  3a| . . .  .   .   | .  .  . | . . .  3a  .   | .  3  . | . . . ---------+---------+-----  3* .  . | .  3  . | 3b. .  .  .  3 | .  .  3A| 3B. .  3  .  3 | .  3  . | . . . ---------+---------+------  .  .  . | .  .  . | . . .  .  .  . | .  .  . | . . .  .  .  . | .  .  . | . . .`

r4c1 is the only cell that 'sees' both conjugates (a and b) of two cells that share a group (A and B).
emm

Posts: 987
Joined: 02 July 2005

Ok, good. That helped A LOT, EM. But can you help out with one more?

In this one...

Code: Select all
` *-----------------------------------------------------------* | 5     16    7     | 2     9     16    | 3     4     8     | | 2     168   3     | 4     578   168   | 156   17    9     | | 4     168   9     | 15    578   3     | 1256  127   57    | |-------------------+-------------------+-------------------| | 1     5     6     | 7     2     4     | 8     9     3     | | 9     7     2     | 8     3     5     | 4     6     1     | | 8     3     4     | 19    6     19    | 7     5     2     | |-------------------+-------------------+-------------------| | 3     2     15    | 6     4     89    | 159   178   57    | | 7     4     15    | 359   58    2     | 159   138   6     | | 6     9     8     | 35    1     7     | 25    23    4     | *-----------------------------------------------------------*`

using your notation * is the one that is excluded, c is a candidate and ? is the one that I just don't get why it's NOT excluded

Code: Select all
` . . . | .  .   . | .  .  .  . . . | .  5a  . | 5A .  .  . . . | *  c   . | c  .  c -------------------- . . . | .  .   . | .  .  .  . . . | .  .   . | .  .  .  . . . | .  .   . | .  .  . -------------------- . . c | .  .   . | c  .  c  . . c | c  ?   . | c  .  .  . . . | 5b .   . | 5b .  . `

Jeanne
JEAGoodman

Posts: 8
Joined: 13 March 2006

You’ve got it, Jeanne - it is excluded. I really like Havard’s threads on Strong links and Skyscrapers for a simple way of visualising this stuff.

Code: Select all
`.  .  . | *  .  . | . . . .  .  . | .  a----|-A . . .  .  . | *  .  . | . . .  --------+---------+------ .  .  . | .  .  . | . . . .  .  . | .  .  . | . . . .  .  . | .  .  . | . . . --------+---------+------ .  .  . | .  * .  | . . . .  .  . | .  * .  | . . . .  .  . | b-------|-B . .`

Skyscraper is a good technique to use on the 3rd puzzle with the 7s.
emm

Posts: 987
Joined: 02 July 2005

Here's a nice one. It needs a couple colorings:

Code: Select all
`*-----------------------------------------------------------------------------* | 79      8       6       | 1249    5       12479   | 39      14      3479    | | 579     345     349     | 1469    8       14679   | 69      146     2       | | 2       1       49      | 469     3       4679    | 5       8       4679    | |-------------------------+-------------------------+-------------------------| | 46      7       5       | 8       46      3       | 2       9       1       | | 3       2       8       | 469     1       469     | 7       46      5       | | 46      9       1       | 7       2       5       | 8       3       46      | |-------------------------+-------------------------+-------------------------| | 15      6       234     | 12345   9       124     | 13      7       8       | | 8       345     7       | 123456  46      1246    | 1369    25      369     | | 159     35      239     | 12356   7       8       | 4       25      36      | *-----------------------------------------------------------------------------*`
alrocks

Posts: 3
Joined: 19 March 2006

alrocks wrote:Here's a nice one.

Why did you put this in this thread? It looks like a new thread.

Mac
QBasicMac

Posts: 441
Joined: 13 July 2005

QBasicMac wrote:
Why did you put this in this thread? It looks like a new thread.

Mac

So Em, thanks to you I think I'm 96% there. Now my only question is how do you know when something is an A or an a. When I look at the code you just entered, I think that I could have missed it by putting the A on the left.

Jeanne
JEAGoodman

Posts: 8
Joined: 13 March 2006

Oops! Sorry all

Mac
QBasicMac

Posts: 441
Joined: 13 July 2005

No worries, Mac.

Wait, I think I've got it and I got what was bothering me before. The A and B are defined because of their relationship not only to their own pairs, but their relationship to one another? They're not quite a pair, but yet, they're connected. Yes?
JEAGoodman

Posts: 8
Joined: 13 March 2006

JEAGoodman wrote:The A and B are defined because of their relationship not only to their own pairs, but their relationship to one another? They're not quite a pair, but yet, they're connected. Yes?

'A' and 'a' are strongly linked. If one is true, the other is false. If one is false, the other is true.

[edit: As shown on em's diagram,] 'A' and 'B' are weakly linked. If one is true, the other is false. But if one is false, the other may be either true or false.

That the colors in one column are both upper case ("AB") has no meaning. The reasoning would be the same if the colors were "Ab", "aB", or "ab".

Ron
Last edited by ronk on Wed Mar 22, 2006 8:26 pm, edited 1 time in total.
ronk
2012 Supporter

Posts: 4764
Joined: 02 November 2005
Location: Southeastern USA

Next