## HELP!!!!

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

### HELP!!!!

I have no idea other than just guessing.
All I need to do is know just one to really get the rest of the grid:

throbdude

Posts: 8
Joined: 10 January 2006

You've got a naked pair of [56] in row 8.
tso

Posts: 798
Joined: 22 June 2005

Whoops!

Missed that lonely "9" in row 8 .... guess I needed to step away from it for awhile.

Thanks!
throbdude

Posts: 8
Joined: 10 January 2006

### HELP!!!!

First, a very nicely presented grid. Thanks.
Second, another way to see through the puzzle: In the lower right box the top row contains 69 - 59; the middle row contains 56. Thus a 9 has to be in the top row, and that eliminates a 9 from the top row of the bottem left box. I find this approach quite helpful in difficult places in evil puzzles.

Ken
kf-ryan

Posts: 3
Joined: 26 August 2005

### Re: HELP!!!!

kf-ryan wrote:First, a very nicely presented grid. Thanks.

I, on the other hand, pray I never see another puzzle posted like that.

Code: Select all
`+------------+---------+------------+| 59  69  56 | 4  7  8 | 2   1   3  || 8   3   2  | 1  6  5 | 7   4   9  || 4   7   1  | 9  2  3 | 5   6   8  |+------------+---------+------------+| 6   4   3  | 7  5  9 | 1   8   2  || 7   1   8  | 2  3  4 | 69  59  56 || 2   5   9  | 6  8  1 | 4   3   7  |+------------+---------+------------+| 59  8   7  | 3  1  2 | 69  59  4  || 1   69  56 | 8  4  7 | 3   2   56 || 3   2   4  | 5  9  6 | 8   7   1  |+------------+---------+------------+`

is is easier to paste into scratchpads.

Although, true, this one can be easily solved from just staring at the display. So the use of the colorful image is fine in this exact thread. Although I wonder if images stay around as long as threads do. I can imagine the day this thread has a blank image.

Well, my display will still be there

Mac
QBasicMac

Posts: 441
Joined: 13 July 2005

### Re: HELP!!!!

Ken wrote:First, a very nicely presented grid. Thanks.
Second, another way to see through the puzzle: In the lower right box the top row contains 69 - 59; the middle row contains 56. Thus a 9 has to be in the top row, and that eliminates a 9 from the top row of the bottem left box. I find this approach quite helpful in difficult places in evil puzzles.

Ken

This technique is referred to as Locked Candidates, where a candidate ( in this case 9) is locked to a certain position in this case Block 9 Row 7, so 9 can be eliminated from the rest of Row 7 not in Block 9.

For more techniques check out
http://www.angusj.com/sudoku/hints.php
http://www.simes.clara.co.uk/programs/sudokutechniques.htm
Crazy Girl

Posts: 189
Joined: 08 November 2005

Here is another puzzle that I have no clue as to what to do next.

I imagine I have to use one of those clever X or XY tricks, but really don't know where to look right now.

Code: Select all
`7    3     258 | 268    258  9    | 468 158  145259  2589  6   | 28     4    1    | 7   589  34    89    1   | 367    578  367  | 689 2    59---------------+------------------+---------------1259 2459  7   | 249    3    8    | 49  19   61269 24689 289 | 2479   2579 2457 | 489 3    124793    2489  289 | 1      6    247  | 5   789  2479---------------+------------------+---------------259  1     259 | 246789 2789 2467 | 3   5679 5798    5679  4   | 367    1    367  | 2   5679 579269  2679  3   | 5      279  267  | 1   4    8`

throbdude

Posts: 8
Joined: 10 January 2006

Hi throbdude,

You've missed a Hidden Single in Column6

But the next step you're after is a HIDDEN Triple in Column 9

Tarek

tarek

Posts: 2699
Joined: 05 January 2006

Hey ... good call on the hidden single!!!!

But, I don't know what a hidden Triple looks like or what you do with it?

Is it the 579? Doesn't there have to be 3 of them? I only see 2.

Code: Select all
`7    3     258 | 268    258  9    | 468 158  145259  2589  6   | 28     4    1    | 7   589  34    89    1   | 367    578  367  | 689 2    59---------------+------------------+---------------1259 2459  7   | 249    3    8    | 49  19   61269 24689 289 | 2479   279  5    | 489 3    124793    2489  289 | 1      6    247  | 5   789  2479---------------+------------------+---------------259  1     259 | 246789 2789 2467 | 3   5679 5798    5679  4   | 367    1    367  | 2   5679 579269  2679  3   | 5      279  267  | 1   4    8 `
throbdude

Posts: 8
Joined: 10 January 2006

The 579 is actually a Naked Triple (one 59 + two 579s), which means that you can eliminate 5, 7 and 9 from the rest of the cells in the column.

The hidden one, which IMHO is less obvious to find, is 124. Combined, these three candidates only occupy three different cells, which means that you can eliminate the other candidates in those three cells.

The net result of applying either of these two techniques is identical, though.
vidarino

Posts: 295
Joined: 02 January 2006

Yes yes ...I see that now ... and the 259 in column 1 too. Mmmmm.

Column 2 looks confusing for a 289 triple ...I'm guessing that I can't apply anything to that one.

In any case, I now have a new tool in my belt now. Thanks!
throbdude

Posts: 8
Joined: 10 January 2006

### HELP!!!

throbdude wrote:"Yes yes ...I see that now ... and the 259 in column 1 too. Mmmmm.
Column 2 looks confusing for a 289 triple ...I'm guessing that I can't apply anything to that one..."

Hi throbdude,
If you are wondering whether the 259 in column 1 is a triple the answer is NO. A triple, whether "naked" or "hidden", requires three candidates or a combination of these same candidates, to appear only in three cells of a unit (row, column or box). In column 1 these three candidates appear in five cells. For similar reasons the 289 in column 2 isn't a triple either. The angusj link suggested above by Crazy Girl provides good examples to help identify triples.

Cec
Cec

Posts: 1039
Joined: 16 June 2005

### Got another one that has me stumped!!

While I admit I don't have enough solving tools in my pocket yet, this one seems very difficult.
Am I missing something basic or do I need a new tool to figure this one out?
Code: Select all
` *-----------*   *--------------------------------------------------* |541|326|987|   | 5    4    1    | 3    2    6    | 9    8    7    | |769|851|243|   | 7    6    9    | 8    5    1    | 2    4    3    | |328|974|651|   | 3    2    8    | 9    7    4    | 6    5    1    | |---+---+---|   |----------------+----------------+----------------| |9.4|..7|528|   | 9    13   4    | 16   136  7    | 5    2    8    | |857|4.2|.96|   | 8    5    7    | 4    13   2    | 13   9    6    | |6.2|598|7.4|   | 6    13   2    | 5    9    8    | 7    13   4    | |---+---+---|   |----------------+----------------+----------------| |49.|7.5|8.2|   | 4    9    36   | 7    16   5    | 8    13   2    | |28.|.49|.75|   | 2    8    36   | 16   4    9    | 13   7    5    | |175|283|469|   | 1    7    5    | 2    8    3    | 4    6    9    | *-----------*   *--------------------------------------------------*`
throbdude

Posts: 8
Joined: 10 January 2006

I think u can solve using remote pair.
Kent

Posts: 98
Joined: 28 February 2006

throbdude,

This is a BUG+1 grid which is explained in this link www.sudoku.com/boards/viewtopic.php?t=2352. Basically if r4c5 were also a bivalue cell, like the rest of the unsolved cells, then the puzzle would not have a unique solution. Any candidate in r4c5 that appears only twice in a group which includes that cell can be excluded, which will leave only a single possible candidate in that cell. Another way to look at it is the value in r4c5 that appears three times in a group must be assigned to that cell. r4c5 must be 1 in either case.

Tracy
TKiel

Posts: 209
Joined: 05 January 2006

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