     Sudoku Solution Path   Copyright © Kevin Stone R2C2 can only be <6> R1C5 is the only square in row 1 that can be <5> R2C3 is the only square in row 2 that can be <3> R4C6 is the only square in row 4 that can be <5> R5C6 is the only square in row 5 that can be <6> R6C4 is the only square in row 6 that can be <3> R5C9 is the only square in row 5 that can be <3> R6C5 is the only square in row 6 that can be <9> R2C7 is the only square in row 2 that can be <9> R3C4 is the only square in row 3 that can be <9> R5C1 is the only square in row 5 that can be <9> R5C2 is the only square in row 5 that can be <5> R7C1 is the only square in row 7 that can be <5> R8C3 is the only square in row 8 that can be <6> R9C7 is the only square in row 9 that can be <5> R9C9 is the only square in row 9 that can be <9> Squares R4C3 and R6C3 in column 3 form a simple locked pair. These 2 squares both contain the 2 possibilities <47>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the column.    R1C3 - removing <4> from <248> leaving <28> R1C1 is the only square in row 1 that can be <4> Intersection of row 1 with block 3. The value <1> only appears in one or more of squares R1C7, R1C8 and R1C9 of row 1. These squares are the ones that intersect with block 3. Thus, the other (non-intersecting) squares of block 3 cannot contain this value.    R3C8 - removing <1> from <12478> leaving <2478>    R3C9 - removing <1> from <127> leaving <27> Intersection of column 8 with block 9. The value <1> only appears in one or more of squares R7C8, R8C8 and R9C8 of column 8. These squares are the ones that intersect with block 9. Thus, the other (non-intersecting) squares of block 9 cannot contain this value.    R7C9 - removing <1> from <127> leaving <27>    R8C7 - removing <1> from <1278> leaving <278> R1C9 is the only square in column 9 that can be <1> Intersection of block 7 with row 9. The value <2> only appears in one or more of squares R9C1, R9C2 and R9C3 of block 7. These squares are the ones that intersect with row 9. Thus, the other (non-intersecting) squares of row 9 cannot contain this value.    R9C5 - removing <2> from <128> leaving <18> Squares R3C6 and R7C6 in column 6 and R3C9 and R7C9 in column 9 form a Simple X-Wing pattern on possibility <2>. All other instances of this possibility in rows 3 and 7 can be removed.    R3C1 - removing <2> from <12> leaving <1>    R7C4 - removing <2> from <248> leaving <48>    R3C8 - removing <2> from <2478> leaving <478>    R7C8 - removing <2> from <1278> leaving <178> R3C2 can only be <8> R9C1 can only be <2> R1C3 can only be <2> R9C3 can only be <8> R9C5 can only be <1> R1C7 can only be <8> R4C7 is the only square in row 4 that can be <1> R6C7 can only be <7> R6C3 can only be <4> R8C7 can only be <2> R5C8 can only be <2> R8C5 can only be <8> R7C9 can only be <7> R5C4 can only be <8> R2C8 can only be <4> R6C6 can only be <1> R4C3 can only be <7> R7C2 can only be <1> R3C9 can only be <2> R8C8 can only be <1> R5C5 can only be <7> R7C4 can only be <4> R8C2 can only be <7> R7C8 can only be <8> R2C5 can only be <2> R3C8 can only be <7> R3C6 can only be <4> R7C6 can only be <2> R4C4 can only be <2> R4C5 can only be <4>    