The New Sudoku Players' Forum

[alanh]

I've got this far and now completely stuck. Help:

5--|---|---
4-1|-7-|-56
9-8|4-5|---

21-|--3|-9-
--5|2-9|6--
-49|8--|-2-

--2|6-4|573
7-3|-2-|-64
--4|---|2-9

I have narrowed cells in row 8 as two pairs of 18 and 59
Cheers
Alan

[Pi]

I couldn't find the sudoku in the sunday times today, could you tellme where it is?

[Pi]

I ran it into my PC and it is definateley possible, although my PC only uses trial and error, i can confirm that you are correct up to that point, i will work on how to proceed

[Pi]

Cracked it there is an X-wing between rows 2 and 8

An X-wing of 8's

[fhm]

only gets you 2 numbers further on

5--|---|---
4-1|-7-|-56
9-8|4-5|---

21-|--3|-98
--5|2-9|6--
-49|8--|-25

--2|6-4|573
7-3|-2-|-64
--4|---|2-9

there must be something else I'm missing

[Pi]

I know i am still trying

[Pi]

Could somebody tell me what a swordfish is, there might be one of those in it?

[alanh]

Thanks for the X-Wing PI; this got me the 8 and 5 too. But still working on it!

[Pi]

OK another breakthrough

Look at every number that can be a six

If you do a little bit of trial end error in the sixes you will find that the cell in collum 1, row 6 cannot be a six because if it was then the cell in collum 6, row 6 would also have to be a six, violating the puzzle, therefore collum 1 row 6 is a 3

OK?

[Bernard Stay]

I'm not very happy about all this. Is there or is there not a purely logical process to solve this puzzle? If not, it doesn't really interest me. I did complete it, but only by employing a sort of double or compound X-wing, involving 6 (rather than 4) 8s - perhaps that is a 'swordfish'(?).

[zebedeezbd]

a sort of double or compound X-wing, involving 6 (rather than 4) 8s - perhaps that is a 'swordfish'(?).

It certainly sounds like a swordfish, Bernard.

[Karyobin]

More importantly, it seems The Sunday Times are printing genuinely challenging sudoku, rather than the fill-the-blanks-Fiendish offered by its daily counterpart.

All hail Superior Sudoku.


P.S. By the way, you didn't need a swordfish for this one, the crux is a particularly nasty hidden triple of {4,8,9} in block three. Find this, eliminate a '3' in block 2 and Robert is, as they say, a sibling of one of those two infinitely generous members of the race who spawned you.

[silvercar]

Thanks for the hints, eliminating the 3 in row 3 column 5 exposes a double in column 5 and opens it up.

[Karyobin]

That puts the 3 for row 3 in block 3, so eliminating the 3 from row 3 columns 2 & 5.

No it doesn't. It removes the 3's from r3c2 and r3c5 certainly, but there's still possibilities in block 2,r1 for 3's.

There should be a naked pair of 1's and 6's in column 5.

[Edited - Hah! You changed it, you naughty boy! Now my post looks weird. Never mind eh?]

[silvercar]

Naughty girl not naughty boy!

I admit I edited it, but I was refering to the naked pair of 1 and 6 in column 5 when I said it opened it up.