PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Sudoku GP Round 7, plus two hidden themes related to 7
(Note: this puzzle was originally created for the Sudoku Grand Prix but after testing was judged too hard and too puzzle-based for the competition. It is an excellent puzzle, and we are proud to showcase it here.)

Author/Opus: This is the 40th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Standard Sudoku rules. Also, standard Skyscrapers rules. Additionally, the cells in gray are “underground” and cannot be seen by any of the outside skyscraper clues (think of them as starting with a negative sign if necessary). As an example, the 3 on the left of row 2 refers only to seeing three buildings in columns 2 through 9, even if there is a 9 in column 1 as that 9 cannot be seen.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 7:00, Master = 10:00, Expert = 20:00

Solution: PDF

Note: Follow this link for our first Basement Skyscraper Sudoku. Follow this link for other less common variations of Sudoku and this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 54th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Variation of Sudoku rules. Every given clue is lying. The correct value is either one more or one less than the given clue. (1 clues cannot become 0, and 9 clues cannot become 10.)

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 5:30, Master = 8:00, Expert = 16:00

Solution: PDF

Note: Follow this link for classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Diamonds

Author/Opus: This is the 182nd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Answer String: Enter the 9th row from left to right, followed by a comma, followed by the 9th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 2:20, Master = 3:30, Expert = 7:00

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Desperately Seeking Seven (Note: the shading of the “7” shaped region is just for artistic purposes.)

Author/Opus: This is the 173rd puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules (no repeats in any rows, columns, or bold regions). The digit range is 1-7.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 1:15, Master = 2:00, Expert = 4:00

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between Sudoku number entry mode and a shading mode to mark the top grid.)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 17th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Variation of Sudoku rules. Each number in the top grid must be moved either up, down, left, or right the same number of cells as that number’s value without crossing the border of the grid. Numbers must all land on unique spots, but unlike in normal Hamle numbers may be adjacent after moving and white areas may not all be connected. Then solve the resulting sudoku. (Note: It is possible for a number to have two valid movement options in the solution; it is only required that at least one direction of movement exists for each number.)

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 5th row from left to right.

Time Standards (highlight to view): Grandmaster = 9:30, Master = 15:00, Expert = 30:00

Solution: PDF

Note: Follow this link for other less common variations of Sudoku. Many specific variations of Sudoku have their own categories in the sidebar to the left. Follow this link for classic Sudoku.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Flyers

Author/Opus: This is the 169th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Answer String: Enter the 6th row from left to right, followed by a comma, followed by the 9th row from left to right.

Time Standards (highlight to view): Grandmaster = 5:30, Master = 11:00, Expert = 22:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Solve Me, I’m Irish

Author/Opus: This is the 94th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Variation of Sudoku rules. Instead of the digits 1-9, use the letters in “SHIRT PACK”.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 8th row from left to right. Use capital letters (i.e. “SHIRTPACK”) when entering each row.

Time Standards (highlight to view): Grandmaster = 2:15, Master = 4:00, Expert = 8:00

Solution: PDF

Note: Follow this link for other less common variations of Sudoku. Many specific variations of Sudoku have their own categories in the sidebar to the left. Follow this link for classic Sudoku.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Four Y Intersection

Author/Opus: This is the 166th puzzle from Thomas Snyder, aka Dr. Sudoku.

Rules: Standard Sudoku rules.

Answer String: Enter the 4th row from left to right, followed by a comma, followed by the 7th row from left to right.

Time Standards (highlight to view): Grandmaster = 2:45, Master = 5:15, Expert = 10:30

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Butterfly — a very elegant 22-given pattern

Author/Opus: This is the 78th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Sudoku rules.

Answer String: Enter the two main diagonals, starting with the 9 digits in the upper-left corner to the lower-right corner, followed by a comma, followed by the 9 digits in the lower-left corner to the upper-right corner.

Time Standards (highlight to view): Grandmaster = 1:45, Master = 2:30, Expert = 5:00

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

(A PDF of the puzzles from week 52 can be found here.)

There will be no new puzzles this week as we look back on the first 52 weeks (and 322 puzzle posts) at GMPuzzles. Over the next six days we will be presenting our “Best of 2013” selections, using data from the FAVE button at the bottom of each post. Because of a variable number of solvers over the year, the selection process included raw FAVE counts, FAVE/solver ratios, and internal discussions when those values brought up ties. Today, we present the nominees in our toughest category (with 77 entries) of BEST SUDOKU:

Big and Small from April was a Classic Sudoku with an uncommon separation of givens that also affected the logic of the solve.

Start Small from May was a Tile Sudoku that many found to be a good pedagogical example for how to solve this style of puzzle.

Boxed In from January was a Thermo-Sudoku with an interesting visual pattern but no givens. The logical path was highly influenced by the “box” theme and many solvers appreciated the very first required deduction.

It’s Sudoku Time from December was a late nominee but a popular one. This arrow sudoku resembles a clock with just 5 givens (at 12, 3, 6, and 9) to get the solver started.

And, by absolute vote count, the favorite sudoku of 2013 is:
Jekyll and Hyde, a consecutive sudoku from February that merges that genre with non-consecutive puzzles with a half empty/half full kind of theme.

The “Best Sudoku of 2013” are all gathered together in this PDF.

Tomorrow we will announce our best number placement puzzles from 2013.