PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: Magic Squares

Author/Opus: This is the 32nd puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Place the digits in the indicated range (1-9) in some of the cells so that no digit is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 7:15, Master = 20:00, Expert = 40:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Japanese Sums puzzles.

This year, we have started to have some extra difficult Sunday Stumpers, about once a month. These will be quite tough puzzles, but with a logical path to be found (and solution videos to help). This seventh Sunday Stumper is a Japanese Sums (Cipher) puzzle with a hidden theme.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry, sudoku, and shading modes. Note that any extra numbers (in green, blue, or red) or shaded cells outside the grid will interfere with solution checking. So we suggest using the Number mode in black to write notes over the outside clues or in the cipher box below the grid; make sure only blue digits are inside the 11×11 grid and not outside the grid.)

Theme: Hidden

Author/Opus: This is the 203rd puzzle from our contributing puzzlemaster Murat Can Tonta.

Rules: Place the digits 1-9 in some of the cells, so that no digit is repeated in any row or column. Also, all numbers are encrypted with J, A, P, N, E, S, U, M, H, D letters and each letter represents a different digit from 0 to 9. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell. Single-digit clues cannot be a 0, and also multi-digit clues cannot start with a 0. A question mark indicates a sum value of unknown size, and can be single- or multi-digit.

Or see this (non-cipher) example of Japanese Sums:

Difficulty: 5 stars

Time Standards (highlight to view): Grandmaster = 27:30, Master = 37:00, Expert = 1:14:00

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Japanese Sums puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: Stopped on the Way Back

Author/Opus: This is the 211th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Place the digits 1-9 in some of the cells, so that no digit is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell. A ? can represent any sum of 1 or larger.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 10:00, Master = 19:15, Expert = 38:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Japanese Sums puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: Multiples of 3

Author/Opus: This is the 27th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Place the digits 1-7 (1-9 for the example) in some of the cells, so that no digit is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell.

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 4:00, Master = 8:45, Expert = 17:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Japanese Sums puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: Double Clues

Author/Opus: This is the 335th puzzle from our managing editor Serkan Yürekli.

Rules: Place the digits 1-6 (1-9 for the example) in some of the cells, so that no digit is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell.

Difficulty: 3 stars

Time Standards (highlight to view): Grandmaster = 4:00, Master = 5:15, Expert = 10:30

Solution: PDF; a solution video is also available here.

Note: Follow this link for other Japanese Sums puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: All Clues are Different Clues (for Randy Rogers)

Author/Opus: This is the 162nd puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Place the digits 1-7 (1-9 for the example) in some of the cells, so that no digit is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell. A ? can represent any sum 1 or larger.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 3rd row from left to right. Use a capital X for empty cells.

Time Standards (highlight to view): Grandmaster = 4:00, Master = 5:30, Expert = 11:00

Solution: PDF

Note: Follow this link for other Japanese Sums puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: Sum of 1 & 2 (for Randy Rogers)

Author/Opus: This is the 146th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Place the digits 1-9 in some of the cells, so that no digit is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent digit groups in that row or column, in order. Each sum is separated by at least one unused cell.

Answer String: Enter the 1st row from left to right, followed by a comma, followed by the 10th row from left to right. Use a capital X for empty cells.

Time Standards (highlight to view): Grandmaster = 18:00, Master = 32:00, Expert = 1:04:00

Solution: PDF

Note: Follow this link for other Japanese Sums puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: Clue Symmetry and Logic

Rules: Hybrid of Easy as ABCD and Japanese Sums puzzle types. Fill some cells with digits 1-5 so that each row and column contains each digit from 1 to 5 exactly once as well as two empty cells. Numbers outside the grid indicate the sum of all digits in the first connected group in that direction as in a Japanese Sums puzzle. For example, the row X345X12 could have a 12 clue on the left or a 3 on the right. Or see here.

Answer String: Enter the marked rows from left to right, separating the two rows by a comma. Use an X (capital letter) for each empty square.

Time Standards (highlight to view): Grandmaster = 3:30, Master = 4:15, Expert = 8:30

Solution: PDF

Note: Follow this link for other Japanese Sums puzzles.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between number entry and shading modes.)

Theme: Clue Symmetry and Logic

Author/Opus: This is the 127th puzzle from our contributing puzzlemaster Serkan Yürekli.

Rules: Hybrid of Japanese Sums and Latin Squares. Place a digit from 1-6 (1-4 in the example) into some cells so that each digit appears exactly once in each row and column. Numbers outside the grid indicate the sums of all adjacent digits in order in that row or column.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 8th column from top to bottom. Use a capital X for empty cells.

Time Standards (highlight to view): Grandmaster = 4:45, Master = 7:30, Expert = 15:00

Solution: PDF; a solution video is available here.

Note: Follow this link for other Japanese Sums puzzles.

Our recent week of Japanese Sums puzzles is gathered together in this PDF and the solutions are in this PDF. More Japanese Sums puzzles (alongside five other genres) can be found in Grandmaster Puzzles Quarterly: Volume 4, which we recently released.

The daily solution videos are on the posts and linked below:

This week we hit a (small) milestone of getting to 1000 subscribers to our YouTube channel. We’re figuring out a good way to mark this occasion, possibly including a 10 by 10×10 puzzle set that I mentioned on the puzzlecrafting video describing my 400th puzzle. We’re also working on some other kinds of content to go alongside the daily solution videos as our goal is to keep growing the audience from here.

We’ll be back in a few minutes with a tough Sunday Stumper puzzle, and then this coming week will be an easier “Starter Pack” variety mix of puzzles. One of them will be a TomTom puzzle from me, and at the end of the week we will be releasing Starter Pack 3: TomTom by Thomas Snyder, a collection of 36 hand-crafted puzzles for beginners (and others) to get into this interesting puzzle style.