## NEW TECHNIQUE? rule of pairs

Advanced methods and approaches for solving Sudoku puzzles

### NEW TECHNIQUE? rule of pairs

Hi All,
I am a newbie, I just know Sudoku over two months ago. I always come Sudoku.com.au site to solve puzzle every evening 10-11pm after hard working day. At present a lot techniques to solve Sudoku, but I can’t study or understand all (not much time and my English not enough). After I solved puzzle I try to look for rule of numbers on solution then I saw PAIRS – for me that is NEW TECHNIQUE, I don’t know this technique ready or not. I post here and if this technicque ready please show me.

a1 a2 a3 a456,789 a456,789 a456,789 a456,789 a456,789 a456,789
a4 a5 a6 a123,789 a123,789 a123,789 a123,789 a123,789 a123,789
a7 a8 a9 a123,456 a123,456 a123,456 a123,456 a123,456 a123,456

T-1 : Always have at lest 03 pair of numbers in 3 block on the same row or column.
Example :
Code: Select all
`a1   a2   a3     a7  a9           a4  a6 a4   a5   a6     a1       a3      a2  a7  a9a7   a8   a9     a2  a4   a6      a3  a1`

Easy to demonstrate this rule : if a1 & a2 not the same row in block 2&3 then a3 has to the same row with a1 or a2 in block 2&3, continue for row 2&3 => T1
Wow… too simple, but I think sometimes it’s useful to solve puzzle. Can extend this rule more? Maybe, but I am not much time, smart or tool (progamme…) to do this.

Exampe (puzzle from Sudoku.com.au Nov. 10-2006 – tough)
Code: Select all
`8 0 0   0 4 0   0 0 00 9 5   0 0 3   0 0 0 0 0 0   2 0 0   0 0 66 0 0   0 0 0   2 0 0 0 2 0   7 0 1   0 4 0 0 0 3   0 0 0   0 0 97 0 0   0 0 9   0 0 00 0 0   5 0 0   6 8 0 0 0 0   0 2 0   0 0 1`
After some basic technique

Code: Select all
`8      1367      1267       19        4          75        13579       123579     2357124    9         5          6         178        3         1478        127        2478     134    1347      147        2         15789      578       1345789     13579      6                             39        39         458                                    7          6         1                            48        58         2                            13        138        9                            5         137        47                            3         2          6 `
Locked block 2,8
1- On column 6 – block 8 : Based on T-1 (67), (64) impossible => (69), (94), (97)
2- On column 4 – block 2 : Based on T-1 (61), (62) impossible => (21), (69)

Pair (69) => r1c4=9 , r4c4=3, r4c5=9 , r7c4=1 => based on T-1 : on column 4 in block 8 only pair (15) => r4c6=5, r3c5=5, r2c5=1, r1c6=7, r6c5=8, r6c4=4, r8c6=4, r8c5=7 => impossibe

Thus, only pair (12) => r1c4=1, r3c5=9 … solved by some chains more.

My English is too bad, someone can edit and extend this technicque if possible

TTT
Last edited by ttt on Sun Nov 12, 2006 11:52 pm, edited 2 times in total.
ttt

Posts: 185
Joined: 20 October 2006
Location: vietnam

I think your technique is similar to Braid Analysis?
unkx80

Posts: 7
Joined: 26 August 2006

Hi UNKX80,
Thanks ! i don't know "Braid Analysis" before, i will study it ...
ttt

Posts: 185
Joined: 20 October 2006
Location: vietnam