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 Post subject: JFFK 7
PostPosted: Mon Jun 29, 2009 7:36 pm 
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Joined: Sat Jan 17, 2009 8:30 am
Posts: 118
Location: france
My first attempt to solve this puzzle forced me to use some hard moves, but working again on my WT, I realized it could be cracked without too much effort. My rating should not exceed 1.5 and I guess there are many ways to tackle this killer, so I hope you will enjoy it.


JFFK 7

Image

3x3::k:2048:5633:5633:3075:2052:1285:1285:2567:2567:2048:5633:3075:3075:2052:6158:3087:3087:2321:3858:2835:2835:2835:6158:6158:4632:4632:2321:3858:3858:1565:1565:11551:6158:11551:4632:3875:3876:3876:3876:11551:11551:11551:11551:11551:3875:2093:5166:4143:4143:11551:5170:11551:3892:3875:2093:5166:4143:5689:5170:5170:3388:3892:3892:3391:5166:5166:5689:5689:5689:3388:3388:3143:3391:2889:2889:2379:2379:2893:2893:2893:3143:


Solution :


Hidden Text:
658472391
293516487
471398652
384251976
915637824
726849135
132965748
869724513
547183269


SSscore : 2.10 (estimated much lower)

Enjoy !


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 Post subject: Re: JFFK 7
PostPosted: Sun Jul 05, 2009 9:32 am 
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Grand Master
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Joined: Wed Apr 16, 2008 1:16 am
Posts: 1040
Location: Sydney, Australia
Completely stuck with no clue how to go any further. Tag anyone? :bouncy:

JFFK 7

Prelims
i. 8(2)n1: no 4,8,9
ii. 22(3)n1: no 1,2,3,4
iii. 8(2)N2: NO 4,8,9
iv. 5(2)n2 = {14/23}
v. 10(2)n3: no 5
vi. 12(2)n3: no 1,2,6
vii. 9(2)n3: no 9
viii. 11(3)n1: no 9
ix. 6(2)n4 = {15/24}
x. 8(2)n4: no 4,8,9
xi. 20(3)n5: no 1,2
xii. 13(2)n7: no 1,2,3
xiii. 12(2)n9: no 1,2,6
xiv. 11(2)n7: no 1
xv. 9(2)n8: no 9
xvi. 11(3)n8: no 9

1. "45" n8: 1 outie r6c6 - 6 = 1 innie r9c6
1a. r6c6 = (789), r9c6 = (123)

2. "45" n89: 2 outies r6c68 + r9c6 = 12
2a. r6c8 = (345)

3. "45" r9: 2 innies r9c19 = 14 = {59}/[68](no 3,4,7; no 8 in r9c1)
3a. r8c1 = (478), r8c9 = (347)

4. "45" c1: 3 innies r345c1 = 16
4a. hidden killer pair 8,9 in c1 in h16(3) & 13(2)n7 since a h16(3) cannot have both of 8 + 9 = 17
4b. 13(2)n7 = [49/85]
4c. h16(3) must have both 4 & 9 or neither (only other place for 4 & 9 in c1 is 13(2)n7) or 8 = {178/268/349/358}
4d. {178} must have 7 in r5c1 since a 15(3) cage cannot be {17}[7] nor {78}[0] -> no 7 in r34c1

5. h14(2)r9 = {59}: both locked for r9
5a. no 2 or 6 in 11(2)n7
5b. no 4 in r8c9
5c. no 4 in 9(2)n8

6. 11(2)n7 = {38/47} = [4/8..]
6a. Killer Pair 4,8 in 11(2) and r9c1: both locked for n7
6b. {1478/2468/3458} all blocked from 20(4)n4

7. "45" n3: 2 outies r1c6 + r4c8 = 9
7a. r4c8 = (5..8)

8. 22(3)n1 = {589/679}: 9 locked for n1

9. "45" n1: 4 innies r2c3 + r3c123 = 15 and must have 4 for n1
9a. = 4{128/137/236}(no 5)

10. "45" n1: 1 outie r3c4 + 4 = 2 innies r2c3 + r3c1
10a. -> no 4 in r2c3 (IOU)
10b. 4 in n1 only in r3: locked for r3
10c. no 5 in r2c9

11. "45" r12: 2 innies r2c69 = 13 (no 1,2,3; no 4,8 in r2c6)
11a. no 6,7,8 in r3c9

12. "45" c1: 1 outie r4c2 + 1 = r5c1
12a. no 9 in r4c2, no 1 in r5c1

13. "45" n12: 1 outie r4c6 + 5 = 2 innies r1c6 + r3c1
13a. max. 2 innies = [48] = 12 -> max. r4c6 = 7
Marks: "Paste Into" JFFK7 in Sudoku Solver:
Code:
.-------------------------------.-------------------------------.-------------------------------.
| 123567    56789     56789     | 123456789 123567    1234      | 1234      12346789  12346789  |
| 123567    56789     123678    | 123456789 123567    5679      | 345789    345789    4678      |
| 123468    1234678   1234678   | 1235678   12356789  12356789  | 12356789  12356789  1235      |
:-------------------------------+-------------------------------+-------------------------------:
| 12345689  12345678  1245      | 1245      123456789 1234567   | 123456789 5678      123456789 |
| 23456789  123456789 123456789 | 123456789 123456789 123456789 | 123456789 123456789 123456789 |
| 123567    123456789 123456789 | 123456789 123456789 789       | 123456789 345       123456789 |
:-------------------------------+-------------------------------+-------------------------------:
| 123567    1235679   1235679   | 123456789 3456789   3456789   | 123456789 123456789 123456789 |
| 48        1235679   1235679   | 123456789 123456789 123456789 | 123456789 123456789 37        |
| 59        3478      3478      | 123678    123678    123       | 1234678   1234678   59        |
'-------------------------------.-------------------------------.-------------------------------'
Cheers
Ed


Last edited by Ed on Sun Jul 05, 2009 1:08 pm, edited 1 time in total.

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PostPosted: Sun Jul 05, 2009 11:56 am 
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Joined: Mon Apr 21, 2008 9:44 am
Posts: 310
Location: MV, Germany
It's been a while since we did a tag, let the fun begin! :cheesey:

14. Innies R1234 = 20(3) <> 1,2

15. Innies R6789 = 10(3) <> 8,9

16. Innies C9 = 9(2) <> 9; R7C9 <> 4
16a. R1C8 <> 1

17. 15(3) @ R4C9 <> 5{37/19} since they are blocked by R8C9 = (37) and R9C9 = (59)
17a. 15(3) = {168/249/267/456} <> 3 since 8{25/34} blocked by Killer quads (2348,2358) of 9(2) @ C9 + Innies C9 = 9(2)
17b. R6C5 <> 3 (CPE @ N6)
17c. Innies R6789 = 10(3): R6C7 <> 6 because 3 only possible there

Marks:
Code:
.-----------.-----------------------.-----------.-----------.-----------------------.-----------------------.
| 123567    | 56789       56789     | 123456789 | 123567    | 1234        1234      | 2346789     1234678   |
|           |           .-----------'           |           :-----------.-----------'-----------.-----------:
| 123567    | 56789     | 123678      123456789 | 123567    | 5679      | 345789      345789    | 4678      |
:-----------+-----------'-----------------------+-----------'           :-----------------------:           |
| 123468    | 1234678     1234678     1235678   | 12356789    12356789  | 12356789    12356789  | 1235      |
|           '-----------.-----------------------+-----------.           :-----------.           :-----------:
| 12345689    12345678  | 1245        1245      | 3456789   | 34567     | 3456789   | 5678      | 456789    |
:-----------------------'-----------.-----------'           '-----------'           '-----------:           |
| 23456789    123456789   123456789 | 123456789   123456789   123456789   123456789   123456789 | 12456789  |
:-----------.-----------.-----------'-----------.           .-----------.           .-----------:           |
| 123567    | 123456789 | 123456789   123456789 | 124567    | 789       | 123457    | 345       | 124567    |
|           |           |           .-----------+-----------'           :-----------:           '-----------:
| 123567    | 1235679   | 1235679   | 123456789 | 3456789     3456789   | 123456789 | 123456789   1235678   |
:-----------:           '-----------:           '-----------------------:           '-----------.-----------:
| 48        | 1235679     1235679   | 123456789   123456789   123456789 | 123456789   123456789 | 37        |
|           :-----------------------+-----------------------.-----------'-----------------------:           |
| 59        | 3478        3478      | 123678      123678    | 123         1234678     1234678   | 59        |
'-----------'-----------------------'-----------------------'-----------------------------------'-----------'


Last edited by Afmob on Sun Jan 16, 2011 7:20 am, edited 1 time in total.

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 Post subject: Re: JFFK 7
PostPosted: Mon Jul 06, 2009 11:16 am 
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Joined: Wed Apr 16, 2008 1:16 am
Posts: 1040
Location: Sydney, Australia
Thanks Afmob!

There are so many multiples of 5 through r5 and n56. Can anyone make anything of that? The only definite things I can really see about that is step 20 but no eliminations.

15(3) cages at r5c1 and r4c9
45(9) cage at n5
h20(3)r4c579
h10(3)r6c579
6 outies r5 = 30
1 innie r5c9 + 15 = 4 outies r46c57
4 outies n39: r19c6 + r46c8 = 15

Anyhow, a couple of actual eliminations but not much.
18. "45" r123: 4 outies r4c1268 = 19
18a. {1279/1459/1468/2359/2458/3457} all blocked by 6(2)n4 [edit]
18b. h19(4) = {1369/1378/1567/2368/2467} [edit]
18c. 9 in {1369} must be in r4c1 but none of (136) will fit into the 15(3)n1: can't have [096/393] and no 5 in r3c1 for [591]
-> no 9 in r4c1
18d. min. r4c68 = [15] = 6 -> max. r4c12 = 13 -> min. r3c1 = 2

19. 9 in r4 only in h20(3)r4 (step 14) = 9{38/47/56}
19a. CPE -> no 9 in r5c78

20. "45" n56: after taking out h12(2)r6c68 -> r4c468 + r6c4 = 18
20a. note: this is an implied h18(4) cage since it cannot have repeats because of the 45(9)n56. But can't see any way to use this.
20b. The same candidates in the 15(3)r5c1 must be in 3 of the 4 cells of the 45(9) that are in r46c57 with the 4th cell being equal to r5c9 and must be one of r46c5. Can't take that any further.
marks:
Code:
.-------------------------------.-------------------------------.-------------------------------.
| 123567    56789     56789     | 123456789 123567    1234      | 1234      2346789   1234678   |
| 123567    56789     123678    | 123456789 123567    5679      | 345789    345789    4678      |
| 23468     1234678   1234678   | 1235678   12356789  12356789  | 12356789  12356789  1235      |
:-------------------------------+-------------------------------+-------------------------------:
| 1234568   12345678  1245      | 1245      3456789   1234567   | 3456789   5678      456789    |
| 23456789  123456789 123456789 | 123456789 123456789 123456789 | 12345678  12345678  12456789  |
| 123567    123456789 123456789 | 123456789 124567    789       | 123457    345       124567    |
:-------------------------------+-------------------------------+-------------------------------:
| 123567    1235679   1235679   | 123456789 3456789   3456789   | 123456789 123456789 1235678   |
| 48        1235679   1235679   | 123456789 123456789 123456789 | 123456789 123456789 37        |
| 59        3478      3478      | 123678    123678    123       | 1234678   1234678   59        |
'-------------------------------.-------------------------------.-------------------------------'


Last edited by Ed on Tue Jul 07, 2009 8:27 pm, edited 1 time in total.

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PostPosted: Mon Jul 06, 2009 5:32 pm 
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Joined: Mon Apr 21, 2008 9:44 am
Posts: 310
Location: MV, Germany
Here some further small moves: (I hope that step 22a is still acceptable as combo analysis)

21. 11(3) @ R9 <> 7 since {37} is a Killer pair 11(2) @ R9

22. 15(3) @ R6C8: R7C8 <> 1 because R6C8+R7C9 <= 13
22a. Outies C9 = 16(3): R1C8 <> 4 because [439] places (39) in 15(3) @ R6C8
and [457] forces 15(3) @ R6C8 = [573] which is blocked by R8C9 = (37)
22b. 10(2) @ N3: R1C9 <> 6
22c. Innies C9 = 9(2): R7C9 <> 3

23. Innies+Outies N7: -1 = R6C2 - R7C13 -> R6C2 <> 1

Marks:
Code:
.-----------.-----------------------.-----------.-----------.-----------------------.-----------------------.
| 123567    | 56789       56789     | 123456789 | 123567    | 1234        1234      | 236789      123478    |
|           |           .-----------'           |           :-----------.-----------'-----------.-----------:
| 123567    | 56789     | 123678      123456789 | 123567    | 5679      | 345789      345789    | 4678      |
:-----------+-----------'-----------------------+-----------'           :-----------------------:           |
| 234678    | 1234678     1234678     1235678   | 12356789    12356789  | 12356789    12356789  | 1235      |
|           '-----------.-----------------------+-----------.           :-----------.           :-----------:
| 1234568     12345678  | 1245        1245      | 3456789   | 1234567   | 3456789   | 5678      | 456789    |
:-----------------------'-----------.-----------'           '-----------'           '-----------:           |
| 23456789    123456789   123456789 | 123456789   123456789   123456789   12345678    12345678  | 12456789  |
:-----------.-----------.-----------'-----------.           .-----------.           .-----------:           |
| 123567    | 23456789  | 123456789   123456789 | 124567    | 789       | 123457    | 345       | 124567    |
|           |           |           .-----------+-----------'           :-----------:           '-----------:
| 123567    | 1235679   | 1235679   | 123456789 | 3456789     3456789   | 123456789 | 23456789    125678    |
:-----------:           '-----------:           '-----------------------:           '-----------.-----------:
| 48        | 1235679     1235679   | 123456789   123456789   123456789 | 123456789   123456789 | 37        |
|           :-----------------------+-----------------------.-----------'-----------------------:           |
| 59        | 3478        3478      | 123678      123678    | 123         123468      123468    | 59        |
'-----------'-----------------------'-----------------------'-----------------------------------'-----------'


Last edited by Afmob on Sun Jan 16, 2011 7:16 am, edited 1 time in total.

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 Post subject: Re: JFFK 7
PostPosted: Tue Jul 07, 2009 9:53 am 
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Joined: Wed Apr 16, 2008 1:16 am
Posts: 1040
Location: Sydney, Australia
Another 3-ways type step in 26. This is about as desperate as I'm prepared to get. If we don't find anything for a couple of days, can you give us a hint manu?

24. h16(3)r345c1 = {178/268/349/358}
24a. {349} must have 9 in r5c1 -> no 4 in r5c1
24b. -> no 3 in r4c2 (i/o c1 = -1)

25. 20(4)n4 = {1289/1379/1469/1568/2369/2567} ([8]{237}/[4]{367} blocked by 11(2)n7; [4]{259} blocked by r9c1)
25a. = only one of 5/9. This led to finding the next step.

26. no 9 in r6c2. Like this. 9 in r6c2 -> no 5 in 20(4)n4 (step 25a)
26a. 9 in r6c2 ->2 innies = 10 (step 23)-> neither can be 5
26b. -> only 5 remaining in n7 is in r9c1 -> 9 in c1 is in r5c1 but this clashes with 9 in r6c2
26c. max. r6c2 = 8 -> max. r7c13 = 9 (no 9)
marks:
Code:
.-------------------------------.-------------------------------.-------------------------------.
| 123567    56789     56789     | 123456789 123567    1234      | 1234      236789    123478    |
| 123567    56789     123678    | 123456789 123567    5679      | 345789    345789    4678      |
| 23468     1234678   1234678   | 1235678   12356789  12356789  | 12356789  12356789  1235      |
:-------------------------------+-------------------------------+-------------------------------:
| 1234568   1245678   1245      | 1245      3456789   1234567   | 3456789   5678      456789    |
| 2356789   123456789 123456789 | 123456789 123456789 123456789 | 12345678  12345678  12456789  |
| 123567    2345678   123456789 | 123456789 124567    789       | 123457    345       124567    |
:-------------------------------+-------------------------------+-------------------------------:
| 123567    1235679   123567    | 123456789 3456789   3456789   | 123456789 23456789  125678    |
| 48        1235679   1235679   | 123456789 123456789 123456789 | 123456789 123456789 37        |
| 59        3478      3478      | 123678    123678    123       | 123468    123468    59        |
'-------------------------------.-------------------------------.-------------------------------'
Cheers
Ed


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 Post subject: Re: JFFK 7
PostPosted: Tue Jul 07, 2009 3:35 pm 
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Here's a hint - I think (at your own risk):
You're down to 2 possibilities for R9C19;
Hidden Text:
I found that one of them leads to a clash in R2/6C6

cheers

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PostPosted: Tue Jul 07, 2009 5:11 pm 
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Another little combo analysis step:

27. Outies R123 = 19(4) = {1378/1567/2368/2467} since other combos blocked by 6(2) @ R4
27a. R4C12 @ 15(3) <> 4 since 15(3) can neither be 9{24} nor 5{46} and 15(3) cannot have 4 and 7
27b. IOD C1: -1 = R4C2 - R5C1: R5C1 <> 5


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 Post subject: Re: JFFK 7
PostPosted: Wed Jul 08, 2009 7:48 am 
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Thanks Afmob for showing what may be a fault line for this puzzle. Some implied cage blocks combined with combo analysis coming up. Starting to get complicated. If there is an easier way or it can be clearer, please share!

28. 15(3)r4c9 = {168/249/267/456} = [2/6,4/6,..]
28a. 45(9) = all of 2,4,6 -> there is no room elsewhere in n56 for both 4 & 6 nor both 2 & 6 (no elims yet)

29. {2467} in h19(4)r4 (step 27) blocked by step 28a. & 15(3)n1. Like this.
29a. {2467} must have r4c68 = [47] ([46] blocked by step 28a)
29b. this leaves r4c12 as {26}: but no 7 available in r3c1 in 15(3)
29c. no 4 in r4c6

30. {2368} in h19(4)r4 (step 27) blocked by step 28a & 15(3)n1
30a. {2368} must have 6 or 8 in r4c12 for the 15(3)n1 to reach the cage sum
30ai. = {26}[38]: blocked by no 7 in r3c1
30aii. = {28}[36]: blocked by no 5 in r3c1
30aiii. = {36}[28]: blocked by the 15(3)n1 cannot be [6]{36}
30aiv. = {38}[26]: blocked by step 28a
30b. h19(4)r4 = {1378/1567}(no 2)
30c. no 3 in r5c1 (i/o C1 = -1)
30d. 1 & 7 locked for r4

31. 6(2)n4 = {24}: 4 locked for r4
31a. deleted
31b. {258} combo blocked from 15(3)n1 since h19(4)r4 cannot have both 5 & 8 (step 30)
marks:
Code:
.-------------------------------.-------------------------------.-------------------------------.
| 123567    56789     56789     | 123456789 123567    1234      | 1234      236789    123478    |
| 123567    56789     123678    | 123456789 123567    5679      | 345789    345789    4678      |
| 23468     1234678   1234678   | 1235678   12356789  12356789  | 12356789  12356789  1235      |
:-------------------------------+-------------------------------+-------------------------------:
| 13568     15678     24        | 24        35689     13567     | 35689     5678      5689      |
| 26789     123456789 123456789 | 123456789 123456789 123456789 | 12345678  12345678  12456789  |
| 123567    2345678   123456789 | 123456789 124567    789       | 123457    345       124567    |
:-------------------------------+-------------------------------+-------------------------------:
| 123567    1235679   123567    | 123456789 3456789   3456789   | 123456789 23456789  125678    |
| 48        1235679   1235679   | 123456789 123456789 123456789 | 123456789 123456789 37        |
| 59        3478      3478      | 123678    123678    123       | 123468    123468    59        |
'-------------------------------.-------------------------------.-------------------------------'
I'll stop here in case I've been tricked.


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 Post subject: Re: JFFK 7
PostPosted: Thu Jul 09, 2009 6:19 am 
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Afmob has verified the previous few steps [edit: and thanks to Andrew for some corrections]. So, continuing on.

32. r4c4 = (24) -> 45(9)n56 must have at least one of 2 or 4 in n6 -> {249} combo blocked from 15(3)r4c9
32a. 15(3)r4c9 = {168/267/456}(no 9)

Looks like it might be cracked now so will miss lots of clean-up.
33. r9c9 = 9 (hsingle c1)
33a. r8c9 = 3
33b. r89c1 = [85]

34. r5c1 = 9 (hsingle c1)
34a. r5c23 = 6 = {15} ({24} blocked by r4c3): both locked for r5 & n4

35. r4c7 = 9 (hsingle n6)

36. no 3 in the two 8(2) cages in c1
36a. 3 only in 15(3)n1 = [438] (only valid permutation) (must have been a hidden single 4 for c1 here too)

37. r4c6 = 1 (hsingle r4)
37a. r4c8 = 7 (hsingle r4)

38. 5 in n1 only in 22(3) = {589}
38a. r1c3 = 8, r12c2 = {59}: both locked for c2

39. r8c3 = 9 (hsingle n7)
39a. r5c23 = [15]

40. 11(2)n7 = {47}: both locked for n7 & r9

41. 20(4)n4 = {236}[9] -> r7c2 = 3
41a. r68c2 = {26}: locked for c2

42. r3c2 = 7 -> r3c34 = 4 = {13}: both locked for r3

43. 8(2)n1 = {26}: both locked for n1 & c1
43a. r67c1 = [71]

44. "45" n3: 1 remaining outie r1c6 = 2, r1c7 = 3
44a. r9c6 = 3
44b. r9c78 = 8 = {26}: both locked for r9 & n9

45. "45" n9: 1 remaining outie r6c8 = 3

46. "45" n7: 4 outies r6c1234 = 23 = [7]{26}[8] (only permutation)
46a. 2 & 6 both locked for n4 & r6
46b. r4c34 = [42]

47. 8 in 45(9)n5 only in n6: locked for n6
47a. 5 in 45(9) only in c5: locked for c5
47b. r12c5 = 8 = {17} only: both locked for c5 and n2

48. 15(3)r4c9 = {456}: all locked for c9 & n6
48a. h9(2)r17c9 = [18]
48b. r7c8 = 4 (cage sum)
48c. r1c8 = 9
48d. r12c2 = [59]
48e. r12c5 = 8 = [71]

49. r23c3 = [31]
49a. r12c4 = 9 = [45]
49b. r6c6 = 9

50. r7c56 = 11 = [65]

Rest are singles.

Turns out that steps 28a, 29 & 30 were the keys ones. Very impressed that manu did this one on his own. :applause: Quite satisfied with that solution. Thanks again manu and Afmob.

Cheers
Ed


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