Still not there yet?

Locked candidate 4 in box 2

Translation: Cells r2c6 and r3c6 have the only 4's in that box. Thus 4's can be eliminated from r4c6 and r5c6 since there can be only one 4 in column 6 and it has to fall in r23c6.

Locked candidate 4 in box 6. Adios 4's in r23c7.

Locked candidate 5 in box 6.

Locked candidate 9 in col 8.

This one is interesting. This time all 9's in column 8 fall in row 7 and row 8 (r78c8). That means the rest of the 9's in that box can be erased.

Naked pair 67 in row 8.

Translation: In row 8 there are two cells that have exactly candidates 6 and 7. So one must be 6 and the other 7. As a result, any other candidates 6 and 7 in row 8 can be erased.

Naked pair 67 in box 9.

Talking about the same pair here, but now noticing that they are in the same box. So the 6 in r7c9 and the 7 in r9c7.

Here are the resultant pencilmarks.

- Code: Select all
`+---------------+-----------------+-------------------+`

| 4 5 168 | 128 18 1278 | 12679 3 26789 |

| 38 7 138 | 9 6 1248 | 12 124 5 |

| 68 9 2 | 3 5 1478 | 167 14 678 |

+---------------+-----------------+-------------------+

| 9 8 45 | 7 134 125 | 2345 6 23 |

| 2567 1 4567 | 256 34 256 | 23459 8 239 |

| 256 3 456 | 2568 48 9 | 245 7 1 |

+---------------+-----------------+-------------------+

| 35 2 359 | 4 7 156 | 8 159 {3} |

| 1 4 589 | 58 2 3 | 67 59 67 |

| 3578 6 3578 | 158 9 158 | 123 125 4 |

+---------------+-----------------+-------------------+

Note the naked single in r7c9. All downhill now.

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