Jan 13th X-treme

Welcome to the world of the unknown. Each day you need to solve <a href="http://www.sudocue.net/xfile.php">two mysteries</a>.<br>Take the X-R-Size or solve the X-Treme problem. Stuck? Found a nice solution? Tell us about it.
sudokuEd
Grandmaster
Posts: 257
Joined: Mon Jun 19, 2006 11:06 am
Location: Sydney Australia
Good work guys. Especially love step 28 - naked triple on those D's again. Nice find Richard.

Here's some moves - then a marks pic. There have been a few typos, so hope we are all at the same spot.

36. r9c6 = 7
36a. r1c3 = 1 -> r1c1 = 7, r9c3 = 4 ->r3c3 = 3 -> r7c7 = 8 -> r3c7 = 5 -> r9c7 = 3 ->r9c6 = 7
36b. r7c3 = 1 -> r1c3 = 4 -> r9c3 = 3 -> r9c6 = 7
36c. both 1's in c3 -> r9c6 = 7

37. r4c56 = [73]

38. r2c9 = 3

39. 7 on D/ in n3 -> no7 r1c8

40. no 9 in r9c1
40a. 9 in r2c2 -> 9 in n4 in c1 -> no 9 r9c1
40b. 9 in r2c8 -> no 9 r9c1

Code: Select all

``````.------------------------.------------------------.------------------------.
| 17      468     14     | 3       5       9      | 2       468     678    |
| 5       79      2      | 6       8       4      | 1       79      3      |
| 468     3468    39     | 7       2       1      | 58      45689   4689   |
&#58;------------------------+------------------------+------------------------&#58;
| 249     249     8      | 5       7       3      | 6       149     149    |
| 3       1       6      | 9       4       8      | 7       2       5      |
| 79      479     5      | 2       1       6      | 348     3489    489    |
&#58;------------------------+------------------------+------------------------&#58;
| 24689   2345689 19     | 148     369     25     | 38      34567   467    |
| 246     568     7      | 148     36      25     | 9       138     146    |
| 168     345689  34     | 148     69      7      | 345     1456    2      |
'------------------------'------------------------'------------------------'
``````
rcbroughton
Expert
Posts: 143
Joined: Wed Nov 15, 2006 1:45 pm
Location: London
Para wrote:still got the problem
I need a new k3yboard

Anyway- 3 more eliminations:

41. Conjugate pairs mean 9 in r2c8 or r6c1 -> no 9 in r6c8
41a. r2c8{97}->r2c2{79}->r3c3{39}->r9c3{34}->r1c3{14}->r1c1{17}->r6c1{79}

42. 3 cannot be in r7c8
42a. 3 either in r6c7 or r6c8. if r6c8 cannot be in r7c8
42a. if in r6c7 -> r6c7<>4 => r9c7=4 -> r9c3<>4 => r1c3=4 -> r1c3<>1 => r1c1=1 -> r1c1<>7 => r1c9=7 -> r2c8<>7 => r7c8=7

43. 3 can't be in r9c2
43a. 3 either in r3c2 or r3c3 if r3c2 -> not in r9c2
43b. if in r3c3 -> not in D\ in n9 -> r9c7=3 -> not in r9c2
Para
Yokozuna
Posts: 384
Joined: Wed Nov 08, 2006 7:42 pm
Location: The Netherlands
Step 43 is nice i love those diagonal empty rectangles.

44. R3C7 is not 8
44a. R3C7=8 -->> R7C7 =3 -->> R8C8 = 8 -->> R1C1 = 1 -->> R1C3=4; R9C1 = 6 -->> no options left for R3C1

45. naked single 5 in R3C7

46. Hidden single 5 in R8C6

47. Naked Single 2 in R7C6

48. Hidden single 2 in R8C1

49. Hidden single 2 in R4C2

50. ALS [R146C1] [R1C3] with common digit 1 eliminates other common digit 4 from R3C1. (it is also an APE, just think ALS sounds nicer )

this is it so far. Dinner time.

can't realy leave this out.

51. naked pair {34} in R9

52. xyz-wing in R8C2, R9C14 eliminates 8 from R9C2

Para
rcbroughton
Expert
Posts: 143
Joined: Wed Nov 15, 2006 1:45 pm
Location: London
Para

Great moves - That solves it then. The key was the 5 in r3c7

53. ALS [r1c1 r2c2 r3c3 r7c7] =1=[r9c1 r8c2] -> no 8 in r7c2

54. 8 now locked in D/ of N7

55. ALS [r1c1 r1c9]=1=[r8c2 r8c5 r8c8] -> no 6 in r8c9

56. Hidden triple {567} in r7c8 r7c9 r9c8 for n9

57. 1 locked in row 8 of N9

58. naked pair {67} at r17c9 in row 9

59. hidden pair {18} r9c14

60. no 1 at r8c8
60a 1 at r1c1 -> no 1 at r8c8
60b. no 1 at r1c1 -> r8c9=1

and the rest is singles.
Para
Yokozuna
Posts: 384
Joined: Wed Nov 08, 2006 7:42 pm
Location: The Netherlands
Nice job on finishing it
rcbroughton wrote: 55. ALS [r1c1 r1c9]=1=[r8c2 r8c5 r8c8] -> no 6 in r8c9
Just wanted to point out this ALS also eliminates the 6 in R9C1. It doesn't matter much here but it might prove important some other day and it would be a shame to miss it

Para