The New Sudoku Players' Forum

[kleinman]

Help anyone.

I got stuck with this one. Can anyone suggest the next move logically. I worked it out by taking a punt but there must be a logical way
**2 51* 649
*46 3** *18
*1* *** 2**

*64 **1 8*7
1** *8* 4*2
289 4** *61

691 *** *2*
7** **9 1**
42* 1*5 9**

[SteveF]

Have a close look at column 6, there is one cell that is the only possibility for one candidate.

Let me know if you need a further clue and I'll let you know what cell (or candidate).

[kleinman]

Sorry I do not get it. please tell me which cell.

In column 6 I see R1 = 7,8
R 2 = 2,7
R3 = 4,6,7,8,
R5 = 3,6
R6 = 3,7
R7 = 3,4,7,8

[simes]

How many 2s do you see there?

S

[kleinman]

Thank you How embarrassing!!!

[kleinman]

I am still not able to solve this. There are too many 3's missing. Can anyone help please

[SteveF]

Have a close look at where 3's can go in box 3. This should allow you to eliminate some 3's as possibilities in row 3.

You will then need to look for several instances of 'possibles locked to a row (or column)', of which the above is an example (and not just for candidate 3's).

[kleinman]

Thank you steveF. Ihave got a pair of 3's for col8 and 9 row 3 but that does not help me much

I will try and show you what I have left. Should I be using x wings or xy chains or something anyway I have as follows though I do not know how to put this properly on the computer, so I hope you can follow

Row1, col1(3,8)col2 (3,7) col6 (7,8)
Row2 col1 (9,5) col5 (2,7,9) col6 (2,7) col7 (5,7)
Row3:col1 (5,8,9) col2(5,7)col3 (6,7,8,9) col4 (4,6,7,9) col5 (4,6,7) col8 (3,5,7) col9 (3,5)

Row4: col1 (3,5) col4 (2,9) col5 (3,2,5,9) col8 (3,5,9)
Row5: col2 (3,5,7) col3 (3,5,7) col4 (6,7,9) col6 (3,6) col8 (3,5,9)
Row 6: col5 (3,5,7) col6 (3,7) col6 (3,5)

Row7: Col 4 (7,8)col5 (3,4,7) col6 (3,4,8) col7 (3,5,7) col9 (3,4,5)
Row8: Col2 (3,5) col3 (3,8,5) col4 (2,6) col5 (2,3,4,6) col8 (3,8) col9 4,6
Row 9: col3 (3,8) col5 (3,6,7) col8 (3,7,8) col9 (3,6)

I am sure it is obvious. I seem to have got blocked by seeing all the 3's

[SteveF]

First point, in your last post you are still showing r2c6 as 2 or 7, but surely from posts from yourself and then Simes it is established this must be a 2?

As I said in my previous post you then need to apply the 'locked to a row (or column)' several times:

Look for where 7's can go in row 6, this should allow some eliminations in box 5.

You will then need to apply this technique again in row 7 and box 9, not necessarily for the same candidate

.... and for column 1, box 1.

.... and for row 7, box 8.

At this point you need to look for a naked triple, which should allow another cell to be completed. Upto this point you certainly do not need x-wings, turbots, or any other advanced techniques.

[kleinman]

Yes sorry, I have r2c6 = 2

I will work through your suggestions. Thank you.

I have a problem with locked to a row. For example in box 4, the 5 could be in row 4 or 5. Do you consider the 5s in row 5 locked? If so why?

Can you tell me what a naked triple is please

[SteveF]

I'm not sure I can help with the example you put forward, it's not one of those I've mentioned in my previous posts.

However to further explain a couple from my posts (from your original position, having put the 2 in r2c6):

In box 3 the only places that a 3 can go is in row3, therefore you can remove candidate 3 from all other cells in row 3 (r3c1, r3c3).

Now look at where a 7 can go in row 6. It can only go in r6c5 and r6c6. But both of these are in box 5. Thus you can remove all other candidate 7's in box 5 (r5c4, r5c6).

These are the main examples of candidates locked to a row / column.

Can I suggest you visit the websites of angusj and Simes (my personal varourites, but there are others v. good examples given in this forum) for further details on this and several other techniques.

[kleinman]

Thank you so much for all your help

I have a great deal to read and digest though I really prefer to play!