R1C6 can only be <1>

R4C1 can only be <3>

R4C9 can only be <9>

R5C4 can only be <1>

R6C1 can only be <2>

R7C7 can only be <6>

R1C4 can only be <7>

R9C6 can only be <4>

R2C5 can only be <6>

R1C5 can only be <5>

R4C5 can only be <8>

R9C4 can only be <8>

R6C5 can only be <4>

R6C9 can only be <1>

R5C5 can only be <3>

R5C6 can only be <9>

R3C7 can only be <1>

R9C7 can only be <9>

R1C7 can only be <8>

R2C9 can only be <3>

R2C2 can only be <1>

R2C8 can only be <9>

R2C1 can only be <8>

R1C1 is the only square in row 1 that can be <9>

R8C9 is the only square in row 8 that can be <8>

R9C9 is the only square in column 9 that can be <7>

R3C3 is the only square in column 3 that can be <7>

R7C9 is the only square in column 9 that can be <5>

R7C1 can only be <4>

R7C3 can only be <2>

R3C1 can only be <6>

R9C3 can only be <3>

R9C8 can only be <2>

R1C3 can only be <4>

R8C2 can only be <7>

R9C5 can only be <1>

R8C8 can only be <3>

R1C8 can only be <6>

R1C2 can only be <3>

R1C9 can only be <2>

R5C8 can only be <4>

R3C9 can only be <4>

R5C9 can only be <6>

R8C1 can only be <1>

R5C2 can only be <5>

R9C1 can only be <5>

R8C5 can only be <2>

R5C1 can only be <7>

R9C2 can only be <6>