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 Post subject: Assassin 253
PostPosted: Thu Jan 03, 2013 9:10 pm 
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Grand Master
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Joined: Wed Apr 16, 2008 1:16 am
Posts: 1044
Location: Sydney, Australia
The inspiration for this cage pattern was this killer on Para's blog here. Have a look at Para's blog - such an incredible variety of puzzles. I don't get time to do any of them. Hatman and Pinata give me enough variety though don't always get to them.... anyway, I started with the same cage structure but different cage values then spent a ridiculous amount of time wrongly solving it a number of times and in the end gave up. It's the V1.60 below if anyone wants to give it a go. I decided to join a couple of cages together and this nice puzzle with a score of 1.45 came out. Used one advanced step and quite a long solution but always felt I was getting somewhere.

Assassin 253
Image

code: paste into solver:
3x3::k:3072:4865:4865:4865:3586:3586:4099:4099:4099:3072:5380:5380:4865:4357:3586:3590:3590:8458:3072:5380:3336:4357:4357:5897:5897:3590:8458:8214:8214:3336:3336:4875:5897:3596:8458:8458:8214:4365:4365:4875:4875:4875:3596:3596:8458:8214:8214:4365:3088:4875:4625:4625:8458:8458:8214:2578:3088:3088:3091:3091:4625:5396:3861:8214:2578:2578:4367:3091:4110:5396:5396:3861:5127:5127:5127:4367:4367:4110:4110:4110:3861:
solution to both puzzles:
+-------+-------+-------+
| 5 9 2 | 1 8 4 | 3 7 6 |
| 4 6 8 | 7 3 2 | 9 1 5 |
| 3 7 1 | 9 5 6 | 8 4 2 |
+-------+-------+-------+
| 1 5 4 | 8 6 9 | 2 3 7 |
| 7 2 6 | 5 1 3 | 4 8 9 |
| 8 3 9 | 2 4 7 | 5 6 1 |
+-------+-------+-------+
| 2 4 7 | 3 9 1 | 6 5 8 |
| 6 1 5 | 4 2 8 | 7 9 3 |
| 9 8 3 | 6 7 5 | 1 2 4 |
+-------+-------+-------+


Assassin 253 V1.60

puzzle pic - might be a spoiler:
Image
code: paste into solver:
3x3::k:3072:4865:4865:4865:3586:3586:4099:4099:4099:3072:5380:5380:4865:4357:3586:3590:3590:4359:3072:5380:3336:4357:4357:5897:5897:3590:4359:3338:3338:3336:3336:4875:5897:3596:4359:4359:3338:4365:4365:4875:4875:4875:3596:3596:4110:4879:4879:4365:3088:4875:4625:4625:4110:4110:4879:2578:3088:3088:3091:3091:4625:5396:3861:4879:2578:2578:4374:3091:4119:5396:5396:3861:5144:5144:5144:4374:4374:4119:4119:4119:3861:
Cheerio
Ed


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 Post subject: Re: Assassin 253
PostPosted: Fri Jan 04, 2013 8:33 pm 
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Joined: Fri May 16, 2008 12:18 am
Posts: 62
Hi Ed

That puzzle I posted is actually the Newbie Killer from Assassin 125.


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 Post subject: Re: Assassin 253
PostPosted: Wed Jan 09, 2013 12:29 am 
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Grand Master
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Joined: Wed Apr 23, 2008 6:04 pm
Posts: 1895
Location: Lethbridge, Alberta, Canada
Thanks Ed for making a nice Assassin based on Para's Newbie Killer cage pattern.

Good to see that Para is still taking an interest in this site. It's also good that Afmob regularly visits this site.

I'll be interested to see what Ed's advanced step was; probably better than my breakthrough in step 23.

Here is my walkthrough for Assassin 253:
Prelims

a) 21(3) cage at R2C2 = {489/579/678}, no 1,2,3
b) 23(3) cage at R3C6 = {689}
c) 10(3) cage at R7C2 = {127/136/145/235}, no 8,9
d) 21(3) cage at R7C8 = {489/579/678}, no 1,2,3
e) 20(3) cage at R9C1 = {389/479/569/578}, no 1,2

1. 45 rule on N12 2 innies R3C36 = 7 -> R3C3 = 1, R3C6 = 6
1a. Naked pair {89} in R3C7 + R4C6, CPE no 8,9 in R4C7
1b. R3C3 = 1 -> R4C34 = 12 = {39/48/57}, no 2,6
1c. 12(3) cage at R1C1 = {237/246/345}, no 8,9
1d. Killer pair 4,7 in 12(3) cage and 21(3) cage at R2C2, locked for N1
1e. 1 in C1 only in R45678C1, locked for 32(7) cage at R4C1, no 1 in R46C2

2. 45 rule on N2 2 remaining innies R12C4 = 8 = {17/35}, no 2,4,8,9
2a. 45 rule on N1 2 remaining innies R1C23 = 11 = {29/38/56}

3. 45 rule on N36 2 innies R36C7 = 13 = [85/94]
3a. 18(3) cage at R6C6 = {459/468/567} (other combinations don’t contain 4 or 5 for R6C7), no 1,2,3
3b. 6 of {468/567} must be in R7C7 -> no 7,8 in R7C7
3c. Omitted, unnecessary after step 6a

4. 45 rule on N47 2 innies R47C3 = 11 = {38/47}/[56/92], no 5,9 in R7C3

5. 45 rule on N89 2 innies R7C47 = 9 = [36/45/54]

6. 18(3) cage at R6C6 = {459/468/567}
6a. 7,8,9 only in R6C6 -> R6C6 = {789}

7. 45 rule on N5 4 innies R46C46 = 26 = {2789/3689/4589/4679/5678}, no 1

8. 12(3) cage at R6C4 = {237/246/345}, no 8,9, clean-up: no 3 in R4C3 (step 4), no 9 in R4C4 (step 1b)
8a. 7 of {237} must be in R7C3 (cannot be [723] which clashes with R12C4), no 7 in R6C4
8b. R7C34 cannot total 9 which clashes with R7C47 = 9 (step 5), CCC -> no 3 in R6C4

9. 45 rule on N9 3 innies R7C7 + R9C78 = 9 = {126/135/234}, no 7,8,9
9a. R7C7 = {456} -> no 4,5,6 in R9C78
9b. 16(4) cage at R8C6 cannot contain more than two of 1,2,3, R9C78 = {123} -> no 1,2,3 in R89C6

10. 45 rule on N47 3 remaining outies R467C4 = 13 = {238/247/346} (cannot be {256} because 2,6 only in R6C4), no 5, clean-up: no 7 in R4C3 (step 1b), no 4 in R7C3 (step 4), no 4 in R7C7 (step 5)
10a. Killer pair 3,7 in R12C4 and R467C4, locked for C4

11. 12(3) cage at R6C4 (step 8) = {237/246}, CPE no 2 in R6C3
11a. R7C4 = {34} -> no 3,4 in R6C4 + R7C3, clean-up: no 8 in R4C3 (step 4), no 4 in R4C4 (step 1b)

12. R7C7 + R9C78 (step 9) = {126/135}, 1 locked for R9 and N9

13. R46C46 (step 7) = {2789/3689}, 9 locked for C6 and N5, 8 also locked for N5

14. 16(4) cage at R8C6 = {1258/1348/1357/2347}
14a. Killer triple 7,8,9 in R46C6 and R89C6, locked for C6

15. 14(3) cage at R1C5 must contain one of 7,8,9 -> R1C5 = {789}

16. 45 rule on N8 3 innies R7C4 + R89C6 = 16 = {358/457}, 5 locked for C6 and N8
16a. R7C4 = {34} -> no 4 in R89C6

17. 45 rule on N3 3 innies R2C9 + R3C79 = 15 = {159/249/258/348} (cannot be {267/357/456} because R3C7 only contains 8,9, cannot be {168} because 1,6 only in R2C9), no 6,7
17a. R3C7 = {89} -> no 8,9 in R23C9

18. 45 rule on N8 2 outies R9C78 = 1 innie R7C4
18a. R7C4 + R9C78 = 3{12}/4{13}, CPE no 3 in R7C9 + R9C5
[With hindsight, this step was available after step 9.]

19. 17(3) cage at R8C4 = {269/467} (cannot be {179} which clashes with 20(3) cage at R9C1, cannot be {278} which clashes with R89C6, ALS block), no 1,8, 6 locked for N8
19a. 7 of {467} must be in R9C5 -> no 4 in R9C5
19b. 9 of {269} must be in R89C4 (cannot be {26}9 which clashes with R6C4) -> no 9 in R9C5

20. 45 rule on C1 1 innie R9C1 = 2 outies R46C2 + 1
20a. Min R46C2 = 5 -> min R9C1 = 6
20b. Max R46C2 = 8, no 7,8,9 in R46C2

21. 17(3) cage at R2C5 = {179/278/359/458}
21a. Killer pair 5,7 in R12C4 and 17(3) cage, locked for N2

22. 16(3) cage at R1C7 = {169/178/259/268/349/358/367} (cannot be {457} which clashes with R2C9 + R3C79)
22a. Killer triple 6,8,9 in R1C23, R1C5 and 16(3) cage, locked for R1
22b. Hidden killer triple 6,8,9 in R1C12, R1C5 and 16(3) cage for R1, R1C12 contains one of 6,8,9, R1C5 = {89} -> 16(3) cage = {178/259/349/358/367} (cannot be {169/268} which contain two of 6,8,9)

23. 19(4) cage at R1C1 (steps 2 and 2a) = {29}{17}/{29}{35}/{38}{17}/{56}{17} -> combined cage 19(4) cage + R1C5 = {29}{17}8/{29}{35}8/{38}{17}9/{56}{17}8/{56}{17}9
23a. 16(3) cage at R1C7 (step 22b) = {349/358/367} (cannot be {178/259} which clash with combined cage), no 1,2, 3 locked for R1 and N3, clean-up: no 8 in R1C23 (step 2a), no 5 in R2C4 (step 2)
23b. 8 in N1 only in 21(3) cage at R2C2 = {489/678}, no 5
23c. 1 in R1 only in R1C46, locked for N2, clean-up: no 7 in R1C4 (step 2)

24. 3 in N1 only in R23C1, locked for C1
24a. 12(3) cage at R1C1 (step 1c) = {237/345}, no 6

25. 20(3) cage at R9C1 = {389/479/569} (cannot be {578} which clashes with R9C6), 9 locked for R9 and N7
25a. 17(3) cage at R8C4 (step 19) = {269/467}
25b. 9 of {269} must be in R8C4 -> no 2 in R8C4

26. 32(7) cage at R4C1 = {1234589/1234679/1235678}, 3 locked for C2 and N4
26a. Max R46C2 = 8 (step 20b) contains 3 -> no 6 in R46C2
26b. R46C2 cannot be {33} = 6 -> no 7 in R9C1 (step 20)

27. 20(3) cage at R9C1 (step 25) = {389/479/569}
27a. 3 of {389} must be in R9C3 -> no 8 in R9C3

28. Hidden killer pair 1,5 in R12C4 and R35C4 for C4, R12C4 contains one of 1,5 -> R35C4 must contain one of 1,5
28a. 45 rule on C1234 2 innies R35C4 = 1 outie R9C5 + 7
28b. R9C5 = {267} -> R35C4 = 9,13,14 = {45}/[81]/{58}/[95] (other combinations don’t contain 1 or 5) -> no 2,6 in R35C4

29. 1 in C9 only in R2456C9, locked for 33(7) cage at R2C9, no 1 in R46C8
29a. 33(7) cage = {1234689/1235679/1245678}, 6 locked for N6

30. 45 rule on N7 3 innies R7C13 + R8C1 = 15 = {168/258/267/456}
30a. 20(3) cage at R9C1 (step 25) = {389/479} (cannot be {569} which clashes with R7C13 + R8C1), no 5,6
30b. R9C1 = R46C2 + 1 (step 20)
30c. R9C1 = {89} -> R46C2 = 7,8 contains 3 = {34/35}, no 2

31. 6 in C1 only in 32(7) cage at R4C1 = {1234679/1235678}, 2 locked for C1
31a. 12(3) cage at R1C1 (step 24a) = {345} (only remaining combination), locked for C1 and N1
31b. 21(3) cage at R2C2 (step 23b) = {678} (only remaining combination), locked for N1, 6 also locked for R2
31c. Naked pair {29} in R1C23, locked for R1 -> R1C5 = 8, R12C6 = 6 = [42], R1C1 = 5, R1C4 = 1, R2C4 = 7 (step 2), clean-up: no 5 in R4C3 (step 1b), no 6 in R7C3 (step 4)

32. 8 in N8 only in R89C6, locked for C6 -> R46C6 = [97], R4C3 = 4, R4C4 = 8 (step 1b), R7C3 = 7 (step 4), R6C4 = 2 (step 13), R7C4 = 3 (cage sum), R7C7 = 6 (step 5), R6C7 = 5 (cage sum), R7C6 = 1, R5C6 = 3

33. R46C2 = [53] = 8 -> R9C1 = 9 (step 20), R9C3 = 3, R9C2 = 8 (cage sum), R7C1 = 2, R7C2 = 4, R7C5 = 9, R8C5 = 2 (cage sum)

34. R7C2 = 4 -> R8C23 = 6 = [15], R8C1 = 6, R89C4 = [46], R89C6 = [85]

35. R89C9 = [34] (hidden singles in N9), R7C9 = 8 (cage sum)

36. R2C9 + R3C79 = 15 (step 17), R3C7 = 8 -> R23C9 = 7 = [52]

37. 1,9 in C9 only in R456C9, locked for N6
37a. 33(7) cage at R2C9 contains 1,2,5,9 = {1235679} (only remaining combination), no 4,8 -> R6C8 = 6, R4C8 = 3

and the rest is naked singles.

Rating Comment:
I'll rate my walkthrough for A253 at Easy 1.5. The analysis in step 23 felt like more than in the 1.25 range.


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 Post subject: Re: Assassin 253
PostPosted: Wed Jan 09, 2013 4:54 am 
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Grand Master
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Joined: Wed Apr 23, 2008 6:04 pm
Posts: 1895
Location: Lethbridge, Alberta, Canada
The V1.60 variant was a bit longer but not much harder.

I'm not sure whether my step 29 was necessary or just a useful shortcut.

Here is my walkthrough for Assassin 253 V1.60:
I was going to start after step 25 of my Assassin 253 walkthrough, but then realised that there were a couple of earlier sub-steps which don’t work for this cage pattern, so I’ve started from the beginning and used as much of my Assassin 253 walkthrough as possible.

Prelims

a) 21(3) cage at R2C2 = {489/579/678}, no 1,2,3
b) 23(3) cage at R3C6 = {689}
c) 10(3) cage at R7C2 = {127/136/145/235}, no 8,9
d) 21(3) cage at R7C8 = {489/579/678}, no 1,2,3
e) 20(3) cage at R9C1 = {389/479/569/578}, no 1,2

1. 45 rule on N12 2 innies R3C36 = 7 -> R3C3 = 1, R3C6 = 6
1a. Naked pair {89} in R3C7 + R4C6, CPE no 8,9 in R4C7
1b. R3C3 = 1 -> R4C34 = 12 = {39/48/57}, no 2,6
1c. 12(3) cage at R1C1 = {237/246/345}, no 8,9
1d. Killer pair 4,7 in 12(3) cage and 21(3) cage at R2C2, locked for N1

2. 45 rule on N2 2 remaining innies R12C4 = 8 = {17/35}, no 2,4,8,9
2a. 45 rule on N1 2 remaining innies R1C23 = 11 = {29/38/56}

3. 45 rule on N36 2 innies R36C7 = 13 = [85/94]
3a. 18(3) cage at R6C6 = {459/468/567} (other combinations don’t contain 4 or 5 for R6C7), no 1,2,3
3b. 6 of {468/567} must be in R7C7 -> no 7,8 in R7C7
3c. Omitted, unnecessary after step 6a

4. 45 rule on N47 2 innies R47C3 = 11 = {38/47}/[56/92], no 5,9 in R7C3

5. 45 rule on N89 2 innies R7C47 = 9 = [36/45/54]

6. 18(3) cage at R6C6 = {459/468/567}
6a. 7,8,9 only in R6C6 -> R6C6 = {789}

7. 45 rule on N5 4 innies R46C46 = 26 = {2789/3689/4589/4679/5678}, no 1

8. 12(3) cage at R6C4 = {237/246/345}, no 8,9, clean-up: no 3 in R4C3 (step 4), no 9 in R4C4 (step 1b)
8a. 7 of {237} must be in R7C3 (cannot be [723] which clashes with R12C4), no 7 in R6C4
8b. R7C34 cannot total 9 which clashes with R7C47 = 9 (step 5), CCC -> no 3 in R6C4

9. 45 rule on N9 3 innies R7C7 + R9C78 = 9 = {126/135/234}, no 7,8,9
9a. R7C7 = {456} -> no 4,5,6 in R9C78
9b. 16(4) cage at R8C6 cannot contain more than two of 1,2,3, R9C78 = {123} -> no 1,2,3 in R89C6

10. 45 rule on N47 3 remaining outies R467C4 = 13 = {238/247/346} (cannot be {256} because 2,6 only in R6C4), no 5, clean-up: no 7 in R4C3 (step 1b), no 4 in R7C3 (step 4), no 4 in R7C7 (step 5)
10a. Killer pair 3,7 in R12C4 and R467C4, locked for C4

11. 12(3) cage at R6C4 (step 8) = {237/246}, CPE no 2 in R6C3
11a. R7C4 = {34} -> no 3,4 in R6C4 + R7C3, clean-up: no 8 in R4C3 (step 4), no 4 in R4C4 (step 1b)

12. R7C7 + R9C78 (step 9) = {126/135}, 1 locked for R9 and N9

13. R46C46 (step 7) = {2789/3689}, 9 locked for C6 and N5, 8 also locked for N5

14. 16(4) cage at R8C6 = {1258/1348/1357/2347}
14a. Killer triple 7,8,9 in R46C6 and R89C6, locked for C6

15. 14(3) cage at R1C5 must contain one of 7,8,9 -> R1C5 = {789}

16. 45 rule on N8 3 innies R7C4 + R89C6 = 16 = {358/457}, 5 locked for C6 and N8
16a. R7C4 = {34} -> no 4 in R89C6

17. 45 rule on N3 3 innies R2C9 + R3C79 = 15 = {159/249/258/348} (cannot be {267/357/456} because R3C7 only contains 8,9, cannot be {168} because 1,6 only in R2C9), no 6,7
17a. R3C7 = {89} -> no 8,9 in R23C9

18. 45 rule on N8 2 outies R9C78 = 1 innie R7C4
18a. R7C4 + R9C78 = 3{12}/4{13}, CPE no 3 in R7C9 + R9C5
[With hindsight, this step was available after step 9.]

[Order of steps changed for simplification.]

19. 20(3) cage at R9C1 = {389/479/569} (cannot be {578} which clashes with R9C6), 9 locked for R9 and N7

20. 17(3) cage at R8C4 = {269/467} (cannot be {179} because 1,9 only in R8C4, cannot be {278} which clashes with R89C6, ALS block), no 1,8, 6 locked for N8
20a. 7 of {467} must be in R9C5 -> no 4 in R9C5
20b. 9 of {269} must be in R8C4 -> no 2 in R8C4

21. 45 rule on C1 1 innie R9C1 = 2 outies R46C2 + 1
21a. Min R46C2 = 3 -> min R9C1 = 4
21b. Max R46C2 = 8, no 8,9 in R46C2

22. 17(3) cage at R2C5 = {179/278/359/458}
22a. Killer pair 5,7 in R12C4 and 17(3) cage, locked for N2

23. 16(3) cage at R1C7 = {169/178/259/268/349/358/367} (cannot be {457} which clashes with R2C9 + R3C79)
23a. Killer triple 6,8,9 in R1C23, R1C5 and 16(3) cage, locked for R1
23b. Hidden killer triple 6,8,9 in R1C12, R1C5 and 16(3) cage for R1, R1C12 contains one of 6,8,9, R1C5 = {89} -> 16(3) cage = {178/259/349/358/367} (cannot be {169/268} which contain two of 6,8,9)

24. 19(4) cage at R1C1 (steps 2 and 2a) = {29}{17}/{29}{35}/{38}{17}/{56}{17} -> combined cage 19(4) cage + R1C5 = {29}{17}8/{29}{35}8/{38}{17}9/{56}{17}8/{56}{17}9
24a. 16(3) cage at R1C7 (step 23b) = {349/358/367} (cannot be {178/259} which clash with combined cage), no 1,2, 3 locked for R1 and N3, clean-up: no 8 in R1C23 (step 2a), no 5 in R2C4 (step 2)
24b. 8 in N1 only in 21(3) cage at R2C2 = {489/678}, no 5
24c. 1 in R1 only in R1C46, locked for N2, clean-up: no 7 in R1C4 (step 2)

25. 3 in N1 only in R23C1, locked for C1
25a. 12(3) cage at R1C1 (step 1c) = {237/345}, no 6

26. Hidden killer pair 1,5 in R12C4 and R35C4 for C4, R12C4 contains one of 1,5 -> R35C4 must contain one of 1,5
26a. 45 rule on C1234 2 innies R35C4 = 1 outie R9C5 + 7
26b. R9C5 = {267} -> R35C4 = 9,13,14 = {45}/[81]/{58}/[95] (other combinations don’t contain 1 or 5) -> no 2,6 in R35C4

27. 45 rule on N7 3 innies R7C13 + R8C1 = 15 = {168/258/267/456}
27a. 20(3) cage at R9C1 (step 19) = {389/479} (cannot be {569} which clashes with R7C13 + R8C1), no 5,6

28. 18(3) cage at R6C6 = {459/468/567}
28a. 45 rule on N7 4(3+1) outies R689C6 + R6C7 = 25 = 21(3)[4]/{20(3)[5] = [9]{57}[4]/[7]{58}5 (because 18(3) cage = [756] when R6C7 = 5) -> R6C6 = {79}
28b. 18(3) cage = {459/567}, 5 locked for C7

29. R1C23 = 11 (step 2a) = {29/56}
29a. Consider combinations for R1C23
R1C23 = {29} => 14(3) cage at R1C5 = 8{24}=> R1C4 = 1 (hidden single in R1)
or R1C23 = {56}, locked for R1 => R1C4 = 1
-> R1C4 = 1, R2C4 = 7 (step 2), clean-up: no 5 in R4C3 (step 1b), no 6 in R7C3 (step 4)

30. Killer pair 8,9 in R4C34 and R4C6, locked for R4

31. 14(3) cage at R1C5 = {248/239}, 2 locked for C6 and N2

32. 45 rule on N3 2 outies R4C89 = 2 innies R3C7 + 2
32a. Min R3C7 = 8 -> min R4C89 = 10, no 1,2 in R4C89

33. 10(3) cage at R7C2 = {136/145/235} (cannot be {127} which clashes with R7C3), no 7
33a. Killer pair 3,4 in 10(3) cage and 20(3) cage at R9C1, locked for N7

34. R7C13 + R8C1 (step 27) = {258/267} (cannot be {168} because R7C3 only contains 2,7), no 1, 2 locked for N7

35. 1 in C1 only in R456C1, locked for N4
35a. R9C1 = R46C2 + 1 (step 21)
35b. Min R46C2 = 5 -> no 4 in R9C1
35c. Max R46C2 = 8, no 7 in R46C2

36. 18(3) cage (step 28b) = {459/567}
36a. R7C13 + R8C1 (step 34) = {258/267} -> R78C1 = {26/58/67}
36b. 19(4) cage at R6C1 = {1567/2368/2458} (cannot be {1279/1369/1378/1459/1468/2359/3457} which don’t contain both of {26/58/67}, cannot be {2467} = [74]{26} which clashes with 18(3) cage) -> R6C12 = [15/24/42/83]

37. Variable hidden killer pair 1,6 in 13(3) cage at R4C1 and 19(4) cage at R6C1 for C1, 13(3) cage cannot contain both of 1,6 -> 19(4) cage must contain at least one of 1,6 -> 19(4) cage = {1567/2368} (cannot be {2458} which doesn’t contain one of 1,6), no 4, 6 locked for C1 and N7
37a. 10(3) cage at R7C2 (step 33) = {145} (only remaining combination), locked for N7
37b. 20(3) cage at R9C1 (step 27a) = {389} (only remaining combination), locked for R9 and N7

38. Naked pair {12} in R9C78, locked for R9 and N9

39. 17(3) cage at R8C4 (step 20) = {467} (only remaining combination) -> R9C5 = 7, R89C4 = {46}, locked for C4 and N8 -> R6C4 = 2, R7C3 = 7, R7C4 = 3, R7C7 = 6 (step 5), R7C6 = 1, R78C1 = [26], R89C6 = [85], R9C9 = 4, R89C4 = [46], R8C23 = [15], R7C2 = 4, R4C6 = 9, R6C6 = 7, R6C7 = 5 (cage sum), R3C7 = 8, R4C34 = [48], R78C5 = [92], R1C5 = 8, R12C6 = 6 = {24} (locked for C6 and N2), R5C46 = [53], R3C4 = 9, R3C2 = 7, R6C2 = 3, R6C1 = 8 (cage sum), R9C1 = 9

40. 2 in N1 only in R1C23 (step 2a) = {29}, locked for R1 and N2 -> R12C6 = [42], R1C1 = 5

41. R2C9 + R3C79 = 15 (step 17), R3C7 = 8 -> R23C9 = 7 = [52], R7C9 = 8, R8C9 = 3 (cage sum)

42. R23C9 = [52] = 7 -> R4C89 = 10 = [37], R1C9 = 6

43. Naked pair {19} in R56C9, locked for N6, R6C8 = 6 (cage sum)

and the rest is naked singles.

Rating Comment:
I'll rate my walkthrough for A253 V1.60 at 1.5. I used the hard analysis step from my A253 walkthrough and a short forcing chain.


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 Post subject: Re: Assassin 253
PostPosted: Fri Jan 11, 2013 7:27 am 
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Grand Master
Grand Master

Joined: Wed Apr 16, 2008 1:16 am
Posts: 1044
Location: Sydney, Australia
Here's how I did A253. Fairly routine but quite different to Andrew's breakthrough. Particularly enjoyed his step 18 and would have loved a step like that to have cracked this puzzle. Our beginning was quite similiar so as has become usual, this if from the first part of Andrew's step 22. Andrew worked out how to use the current release off SS v3.6.1 to "import candidates": copy the "marks" diagram, open A253 in SS, File>Import>Candidates>Okay. Alternatively, you can download the attached SS file which will include all the combo eliminations and hidden cages etc already at the correct spot. A few of you downloaded the last one I did like this so hope you found it worthwhile.

A253
11 more steps:
.-------------------------------.-------------------------------.-------------------------------.
| 234567 235689 235689 | 1357 89 1234 | 123456789 123456789 123456789 |
| 234567 456789 456789 | 1357 12345789 1234 | 123456789 123456789 12345 |
| 23457 45789 1 | 24589 2345789 6 | 89 2345789 2345 |
:-------------------------------+-------------------------------+-------------------------------:
| 123456789 23456 459 | 378 1234567 89 | 1234567 123456789 123456789 |
| 123456789 123456789 23456789 | 12456 1234567 12345 | 123456789 123456789 123456789 |
| 123456789 23456 3456789 | 26 1234567 789 | 45 123456789 123456789 |
:-------------------------------+-------------------------------+-------------------------------:
| 123456789 1234567 267 | 34 1234789 1234 | 56 456789 2456789 |
| 123456789 1234567 234567 | 2469 1234789 578 | 456789 456789 23456789 |
| 6789 3456789 3456789 | 2469 267 578 | 123 123 23456789 |
'-------------------------------.-------------------------------.-------------------------------'


Before Andrew's step 22a above. ie, just first part of 22.

23. 20(3)n7: {578} blocked by r9c6 = (578)
23a. = {389/479/569} = [8->3..]
23b. must have 9 -> 9 locked for r9 and n7

24. "45" on n7: 3 innies r78c1+r7c3 = 15 and must have 2,6 or 7 for r7c3
24a. = {168/258/267/357/456}

25. 8 in n7 is in 20(3) = {389} = [8->3..] (step 23a) or in h15(3) -> 3 in h15(3) must also have 8 or there would be no 8 for n7 -> {357} blocked from h15(3) (Locking-out cages)
25a. = {168/258/267/456}(no 3) = [5/6..]

26. {569} blocked from 20(3)n7 by h15(3) = [5/6..]
26a. = {389/479}(no 5,6)

The key step
27. from step 20. min. r9c1 7 -> min. r46c2 = 6, ie can't have both 2 & 3 in r46c2 (no eliminations yet)
27a. 32(7)r4c1 = {1234589/1234679/1235678}: must have both 2 & 3 -> at least one of 2 or 3 must be in c1
27b. -> {237} blocked from 12(3)n1
27c. 12(3) = {246/345}(no 7) = [5/6..]
27d. must have 4: 4 locked for c1 and n1

28. {56} blocked from h11(2)r1c23 by 12(3)n1 = [5/6..]
28a. = {29/38}(no 5,6) = [8/9..]

29. Killer pair 8,9 in r1 in h11(2)r1c23 + r1c5: both locked for r1

Cracked now:
30. 16(3)n3 = {367} only: all locked for r1 and n3
30a. h11(2)r1c23 = {29} only: both locked for r1 and n1
30b. r1c5 = 8
30c. r12c6 = 6 (cage sum) = [42]
30d. r1c1 = 5
30e. r12c4 = [17] (h8(2)r12c4)
30f. naked pair {68} at r2c23: both locked for n1 & 8 for r2
30g. r3c2 = 7
30h. no 5 in r4c3 (h12(2)r4c34)
30i. no 6 in r7c3 (h11(2)r47c3)

31. h15(3)n7 must have 2 or 7 for r7c3 = {267} only: all locked for n7, 6 locked for c1 and for 32(7): no 6 in r46c2

missing clean-ups from here
32. 20(3)n7 = {389} only: 3 & 8 locked for r9; 3 also for n7

33. r9c78 = {12}: 2 locked for n9 & r9
33a. r9c78 = 3 -> r7c7 = 6 (h9(3)n9)
33b. r7c4 = 3 (h9(2)r7c47)
33c. r6c4 + r7c3 = 9 (cage sum) = [27] only
33d. hidden singles 5 & 8 in n8 -> r2c6 = 8, r9c6 = 5

34. 17(3)n8 = {467} only -> r9c5 = 7
34a. r89c4 = {46}: both locked for c4 and 4 for n8

on from there.
Cheerio
Ed


Attachments:
A253 Andrew WT alt ending from step 22.ssv [102.41 KiB]
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