Sudoku Solution Path    R9C6 can only be <3> R9C4 can only be <1> R1C6 can only be <8> R5C6 can only be <4> R8C6 can only be <6> R2C6 can only be <5> R6C1 is the only square in row 6 that can be <4> R8C4 is the only square in column 4 that can be <7> R2C4 is the only square in column 4 that can be <4> R3C8 is the only square in row 3 that can be <4> R3C7 is the only square in row 3 that can be <5> R9C7 can only be <9> R9C3 can only be <5> R1C3 is the only square in row 1 that can be <9> R8C3 can only be <4> R8C5 can only be <9> R8C2 can only be <1> R7C5 can only be <4> R8C7 can only be <2> R8C8 can only be <5> R1C7 can only be <3> R1C4 can only be <2> R2C7 can only be <8> R3C9 can only be <2> R3C1 can only be <8> R6C9 can only be <1> R2C8 can only be <9> R7C9 can only be <3> R5C7 can only be <6> R7C8 can only be <6> R4C9 can only be <9> R5C4 can only be <3> R7C1 can only be <9> R4C1 can only be <2> R7C7 can only be <1> R4C5 can only be <5> R4C8 can only be <3> R5C3 can only be <8> R4C2 can only be <6> R6C5 can only be <2> R5C2 can only be <9> R5C8 can only be <2> R7C3 can only be <7> R6C2 can only be <5> R5C5 can only be <1> R6C8 can only be <8> R7C2 can only be <8> R3C3 can only be <6> R3C5 can only be <3> R2C3 can only be <2> R2C2 can only be <3> R3C2 can only be <7> R2C5 can only be <6>