dailysudoku.com

[daykart]

While I do not consider myself an "expert", I think I am pretty good at these types of puzzles....but, I always get stumped on the very hard ones.
Discounting the obvious, a case where you do not SEE something, I have a hole in logic that I need help with.
I read the account of Guest for Dec. 20, and do not see it.

If what I wrote below is correct, and there is nothing that is obvious like one number just hanging out there, then I need a "logic crutch"!
Can someone show me the light?

3 _ _ 8 4 5 _ _ 6
_ 6 _ _ _ _ _ _ _
2 _ 4 6 _ _ 7 _ _

1 4 _ 9 _ 6 3 _ 8
6 _ _ _ 8 _ _ _ 4
_ _ 3 4 1 2 6 9 7

_ _ 6 _ _ _ 8 _ 2
_ _ _ _ _ _ _ 6 _
_ _ _ 1 6 8 _ _ 5

r1c2 1,7,9 c3 1,7,9 c7 1,2,9 c8 1,2
r2c1 5,8,9 c3 1,5,8,9 c4 2,3,7 c5 2,3,7,9 c6 1,3,7,9 c7 1,4,5,9 c8 1,3,4,5,8 c9 1,3,9
r3c2 1,5,8,9 c5 3,9 c6 1,3,9 c8 1,3,5,8 c9 1,3,9

r4c3 2,7 c5 5,7 c8 2,5
r5c2 2,7,9 c3 2,7,9 c4 3,5,7 c6 3,7 c7 1,2,5 c8 1,2,5
r6c1 5,8 c2 5,8

r7c1 4,5,7,9 c2 1,3,5,9 c4 3,5,7 c5 3,5,7,9 c6 3,4,7,9 c8 1,3,4,7
r8c1 4,5,7,9 c2 1,3,5,8,9 c3 1,5,8,9 c4 2,3,5,7 c5 2,3,5,7,9 c6 3,4,7,9 c7 1,4,9 c9 1,3,9
r9c1 4,7,9 c2 2,3,9 c3 2,9 c7 4,9 c8 3,4,7

[someone_somewhere]

Hi,

2 not in r2c7, not in r2c8, it is in r1c7 or r1c8 (Row on 3x3 Block interaction)
7 not in r2c1, not in r2c3, it is in r1c2 or r1c3 (Row on 3x3 Block interaction)
5 not in r4c3, not in r5c2, not in r5c3, it is in r6c1 or r6c2 (Row on 3x3 Block interaction)
2 not in r8c2, not in r8c3, it is in r9c2 or r9c3 (Row on 3x3 Block interaction)

7 not in r7c2, not in r8c2, not in r8c3, not in r9c2, not in r9c3 because of
it is in r7c1 or r8c1 or r9c1 (Column on 3x3 Block interaction)

1 not in r3c2, 1 not in r3c8, 3 not in r3c8, 9 not in r3c2 because of
Hidden Pair 5 8 in r3c2 and r3c8 (in Row)

5 not in r7c2, 5 not in r8c2, 8 not in r8c2 because of
Nacked Pair 5 8 in r3c2 and r6c2 (same Column)

1 not in r2c3, 1 not in r8c3, 9 not in r2c3, 9 not in r8c3 because of
Hidden Pair 5 8 in r2c3 and r8c3 (in Column)

1 in r1c3 - Unique Vertical

and from here one you can swim alone. Good luck.

see u,