### Easy as Japanese Sums by Salih Alan

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

Theme: Almost All Triples

Author/Opus: This is the 19th puzzle from guest contributor Salih Alan.

Rules: Fill some cells with numbers 1-5 so that each row and column contains each number from 1 to 5 exactly once as well as three empty cells (1-4 and two empty cells in the example). Numbers outside of the grid indicate the sum of all numbers in the first connected group in that direction as in a Japanese Sums puzzle.

Difficulty: 4.5 stars

Time Standards (highlight to view): Grandmaster = 8:30, Master = 17:15, Expert = 34:30

Solution: PDF and solving video.

### Sunday Stumper: Japanese Sums (Battleships) by John Bulten

Since 2021, we have posted 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 of 2022 is a variation of Japanese Sums by John Bulten.

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

Theme: Yamato

Author/Opus: This is the 88th puzzle from our contributing puzzlemaster John Bulten.

Rules: Standard Japanese Sums rules: Place the numbers in the indicated range (1-9) in some of the cells so that no number is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent number 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.

Also, all unused cells must form an unknown fleet of 1-cell wide ships in the grid. Each segment of a ship occupies a single cell, and ships do not touch each other, even diagonally.

Difficulty: 5 stars

Time Standards (highlight to view): Grandmaster = 18:30, Master = 30:00, Expert = 1:00:00

Solution: PDF and solving video.

### Japanese Sums by Sam Cappleman-Lynes

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

Theme: Why was 6 Afraid of 7?

Author/Opus: This is the 10th puzzle from guest contributor Sam Cappleman-Lynes.

Rules: Place the numbers in the indicated range (1-8) in some of the cells so that no number is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent number 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 = 12:00, Master = 20:00, Expert = 40:00

Solution: PDF and solving video.

### Japanese Sums by Prasanna Seshadri

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

Theme: Twenty20 Vision

Author/Opus: This is the 238th puzzle from our contributing puzzlemaster Prasanna Seshadri.

Rules: Place the numbers in the indicated range (1-9) in some of the cells so that no number is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent number groups in that row or column, in order. Each sum is separated by at least one unused cell. The adjacent question marks (??) show two-digit numbers, not two groups)

Difficulty: 3.5 stars

Time Standards (highlight to view): Grandmaster = 6:00, Master = 9:15, Expert = 18:30

Solution: PDF and solving video.

### Japanese Sums by Ashish Kumar

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

Theme: Doubles

Author/Opus: This is the 96th puzzle from our contributing puzzlemaster Ashish Kumar.

Rules: Place the numbers in the indicated range (1-6) in some of the cells so that no number is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent number 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 = 4:30, Master = 8:15, Expert = 16:30

Solution: PDF and solving video.

### Japanese Sums by Thomas Snyder

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

Theme: Common Denominations

Author/Opus: This is the 415th puzzle from Thomas Snyder, aka Dr. Sudoku.

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

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:30, Master = 4:00, Expert = 8:00

Solution: PDF and solving video.

### Easy as Japanese Sums by Serkan Yürekli

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

Theme: 1 to 10

Author/Opus: This is the 372nd puzzle from our managing editor Serkan Yürekli.

Rules: Fill some cells with numbers 1-4 so that each row and column contains each number from 1 to 4 exactly once as well as two empty cells. Numbers outside of the grid indicate the sum of all numbers in the first connected group in that direction as in a Japanese Sums puzzle.

Difficulty: 2.5 stars

Time Standards (highlight to view): Grandmaster = 2:00, Master = 3:15, Expert = 6:30

Solution: PDF and solving video.

### Japanese Sums by JinHoo Ahn

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

Theme: High Five

Author/Opus: This is the 50th puzzle from our contributing puzzlemaster JinHoo Ahn.

Rules: Place the numbers in the indicated range (1-5) in some of the cells so that no number is repeated in any row or column. Numbers on the outside of the grid indicate the sums of adjacent number 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: 1 star

Time Standards (highlight to view): Grandmaster = 0:40, Master = 1:00, Expert = 2:00

Solution: PDF and solving video.

### Japanese Sums by JinHoo Ahn

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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.

### Sunday Stumper: Japanese Sums (Cipher) by Murat Can Tonta

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.