## Very Hard...

Advanced methods and approaches for solving Sudoku puzzles

### Very Hard...

A week's holiday has not helped me solve this...I can see triplets in row 4 of 357/128 but cannot see any other steps to move this on...

*** 3** 7*2
*5* *27 6*9
*** *** 1*8

**6 **4 *9*
349 *** 561
*** 9** 4**

9*4 *** *15
2** 51* 974
1*5 **9 3*6

(Taken from the Sudoku programme)
Arnie

Posts: 49
Joined: 19 May 2005

You are looking for too complex moves... :)

Take a good look at row 5.

Then take a good look on box 5.

You should be able to fill in 1 number...
Animator

Posts: 469
Joined: 08 April 2005

Bah!... 1 in r4c4... thanks....
Arnie

Posts: 49
Joined: 19 May 2005

How did you come that that conclusion?

I'm stumped at to how you picked that number. Could you outline your thought process please?
Guest

Posts: 312
Joined: 25 November 2005

What are the values for r4c1?

Then ask yourself this: what numbers of box 5 needs to be on row 5? And can therefor be eliminated from r4c1 (it's also in box 5)?
Animator

Posts: 469
Joined: 08 April 2005

ok. I got it.

The possible values for the top left in the centre square are: 1,2,7,8

But, 2,7,8 must be in the centre row of the centre square to make up the row of 1-9.

Therefore, the value must be 1.
Guest

Posts: 312
Joined: 25 November 2005