Nov 30 - Super Hard
Puzzle Copyright © Kevin Stone
Share link – www.brainbashers.com
Reasoning
R1C6 can only be <4>
R7C3 can only be <8>
R9C4 can only be <2>
R9C6 can only be <3>
R1C4 can only be <7>
R5C5 is the only square in row 5 that can be <2>
R5C4 is the only square in row 5 that can be <4>
R5C2 is the only square in row 5 that can be <8>
R8C8 is the only square in row 8 that can be <3>
R8C6 is the only square in column 6 that can be <5>
R7C1 is the only square in row 7 that can be <5>
R7C7 is the only square in row 7 that can be <2>
R2C9 is the only square in column 9 that can be <5>
R1C8 can only be <2>
R1C2 can only be <5>
R3C9 is the only square in column 9 that can be <4>
Intersection of column 3 with block 1. The value <9> only appears in one or more of squares R1C3, R2C3 and R3C3 of column 3. These squares are the ones that intersect with block 1. Thus, the other (non-intersecting) squares of block 1 cannot contain this value.
R2C2 - removing <9> from <1249> leaving <124>
Intersection of column 8 with block 6. The values <59> only appears in one or more of squares R4C8, R5C8 and R6C8 of column 8. These squares are the ones that intersect with block 6. Thus, the other (non-intersecting) squares of block 6 cannot contain these values.
R5C9 - removing <9> from <179> leaving <17>
Squares R4C2<69>, R6C2<19> and R9C2<16> in column 2 form a comprehensive naked triplet. These 3 squares can only contain the 3 possibilities <169>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the column.
R2C2 - removing <1> from <124> leaving <24>
R8C2 - removing <16> from <1246> leaving <24>
Squares R6C2 and R6C8 in row 6 and R9C2 and R9C8 in row 9 form a Simple X-Wing pattern on possibility <1>. All other instances of this possibility in columns 2 and 8 can be removed.
R2C8 - removing <1> from <167> leaving <67>
R5C8 - removing <1> from <179> leaving <79>
Intersection of block 3 with column 7. The value <1> only appears in one or more of squares R1C7, R2C7 and R3C7 of block 3. These squares are the ones that intersect with column 7. Thus, the other (non-intersecting) squares of column 7 cannot contain this value.
R8C7 - removing <1> from <167> leaving <67>
Squares R2C4, R8C4, R2C5 and R8C5 form a Type-4 Unique Rectangle on <89>.
R2C5 - removing <9> from <3689> leaving <368>
R8C5 - removing <9> from <789> leaving <78>
Squares R2C8 (XY), R2C6 (XZ) and R5C8 (YZ) form an XY-Wing pattern on <9>. All squares that are buddies of both the XZ and YZ squares cannot be <9>.
R5C6 - removing <9> from <69> leaving <6>
R5C1 can only be <1>
R2C6 can only be <9>
R2C4 can only be <8>
R5C9 can only be <7>
R3C1 can only be <3>
R6C2 can only be <9>
R5C8 can only be <9>
R7C9 can only be <9>
R6C5 can only be <5>
R4C2 can only be <6>
R6C8 can only be <1>
R4C5 can only be <9>
R9C8 can only be <6>
R7C5 can only be <7>
R8C9 can only be <1>
R8C3 can only be <4>
R9C2 can only be <1>
R2C8 can only be <7>
R8C7 can only be <7>
R8C4 can only be <9>
R3C5 can only be <6>
R2C1 can only be <2>
R3C7 can only be <1>
R2C5 can only be <3>
R3C3 can only be <9>
R2C7 can only be <6>
R4C8 can only be <5>
R8C5 can only be <8>
R8C2 can only be <2>
R2C3 can only be <1>
R2C2 can only be <4>
R8C1 can only be <6>
Today's Sudoku Puzzles
All daily items change at midnight GMT – set your local time zone.
Note: BrainBashers has a Dark Mode option – I recommend not using your browser's dark mode or extensions for BrainBashers