Triangular Sudoku

Experience the Original: 150 TriDoku Puzzles in a Triangular Grid

Refresh your passion for logic with the first-ever collection of TriDoku. If you are tired of standard 3x3 grids, this book introduces a revolutionary triangular architecture that will sharpen your existing skills and force you to learn entirely new solving techniques. Each puzzle is played on a massive triangular grid where nonets are triangles rather than squares, creating a sophisticated mental workout.

The Unique Rules of TriDoku

TriDoku abandons traditional rows and columns in favor of geometric complexity. To solve these grids, you must master several unique constraints:

• Triangular Nonets: Each of the nine large triangles (drawn with thick lines) must contain all numbers from 1 to 9.
• Outer and Inner Edges: The three sides of the large "big" triangle and the three sides of the "inner" triangle must each contain the digits 1 to 9 without repeats.
• The Touching Rule: No two cells that touch—even by a single angle—can contain the same number. A single cell can touch up to 12 adjacent cells, allowing for rapid elimination of candidates.
• The Hexagon Rule: Any six cells forming a hexagon must contain unique digits, providing a powerful secondary deductive tool.

Professional Challenge & Variety

This landmark first edition features 150 puzzles that escalate in complexity, including two elite variants for the advanced solver:

• 10 TriDoku Star (TriDoku X): Features three additional lines where numbers cannot repeat, similar to Diagonal Sudoku.
• 10 Killer TriDoku: The ultimate "beast" of the collection, replacing clues with cages and sums for a deeply satisfying arithmetic challenge.

Expertly Crafted by Djape

As a renowned contributor to The Washington Post, Djape delivers professional-grade logic engineering that ensures every puzzle has a single unique solution reachable without guessing. Printed on high-quality paper in a large 8.5" x 11" format, this collection is the gold standard for anyone seeking a "refreshing" and mathematically rigorous alternative to classic Sudoku.

DJAPE is the author of over 30 puzzle books, ranging from Sudoku variants such as Killer Sudoku and Samurai Sudoku to Hidoku, CalcuDoku and Picross/Hanjie/Griddlers/Nonograms puzzles. Also, Djape contributes regularly to newspapers and magazines across the globe, including The Washington Post. Currently Djape is working on his PhD thesis in Computer Science. Likes sailing, playing bridge and travelling.