dailysudoku.com

[sar]

Hi all -
I'm looking for some help. I have just recently been introduced to Sudoku and have done some reading on the logic of x-wing, swordfish, etc. Still can't figure out what I am missing with this puzzle. The puzzle is Evil # 3.379.900.014 from Websudoku.
Original puzzle is:

008 029 007
000 000 000
040 008 956
090 000 405
000 601 000
306 000 020
412 300 070
000 000 000
609 710 800

I have gotten it to this state:

{15}68; {45}29; {13}{134 7
9{357}{1357}; {45}6{37}; 28{134}
24{37}; 1{37}8; 956

{178}9{17}; {28}{37}{237}; 465
{78}24; 651; {37}9{38}
3{578}6; {89}{49}{457}; {17}2{18}

412; 38{56}; {56}79
{578}{3578}{357}; {29}{49}{2456}; {56}{134}{1234}
6{35}9; 71{245}; 8{34}{234}


Can you please help me with the holes in my logic?
TIA

[keith]

sar,

It took me a while to solve, but this one uses only regular techniques.

First, you have a slight error: The possibility in R6C6 should be <47>, not <457>. If you fix that, then R6C2 must be <5>, and another 13 squares are immediately forced.

Then, you can find the cell which must be <4> in R1, and the puzzle is solved.

I hope this helps,

Keith

Tomorrow, back to work for me, no Sudoku for a few days!

[sar]

Thank you for pointing the error out to me!