The Puzzles of Nobuyuki Yoshigahara

1. Front Matter

   Pages i-xvii

   PDF

2. Introductory Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 1-4

3. Matchstick Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 5-12

4. Maze Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 13-32

5. Algorithmic Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 33-48

6. Combinatorial Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 49-62

7. Digital Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 63-78

8. Number Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 79-98

9. Geometric Puzzles

   • Andy Liu, George Sicherman, Takayuki Yoshigahara

   Pages 99-118

10. Dissection Puzzles

    • Andy Liu, George Sicherman, Takayuki Yoshigahara

    Pages 119-150

11. Other Puzzles

    • Andy Liu, George Sicherman, Takayuki Yoshigahara

    Pages 151-166

12. Back Matter

    Pages 167-170

    PDF

This book convenes a selection of 200 mathematical puzzles with original solutions, all celebrating the inquisitive and inspiring spirit of Nobuyuki “Nob” Yoshigahara – a legend in the worldwide community of mathematical and mechanical puzzles. A graduate from the Tokyo Institute of Technology, Yoshigahara invented numerous mechanical puzzles and published over 80 puzzle books. In 2003, he was honored with the Sam Loyd Award, given by the Association for Games & Puzzles International to individuals who have been made a significant contribution to the world of mechanical puzzles.
In this work, the reader will find some of the most ingenious puzzles ever created, organized in ten categories: Logic, matchstick, maze, algorithmic, combinatorial, digital, number, geometric, dissection, and others. Some of them could rivalry with those found at Mathematical Olympiads tests around the globe; others will work as powerful brain teasers for those with an interest in problem-solving.Math teachers, curious students of any age and even experienced mathematicians with a taste for the fun in science can find in this book unconventional paths to develop their problem-solving skills in a creative way.

• problem solving
• Nobuyuki Yoshigahara
• recreational mathematics
• heuristics
• math puzzles

“This book, wonderfully conceived by Andy Liu, George Sicherman, and Nob's son Takayuki Yoshigahara, contains a selection of 200 of Nob's mathematical puzzles (with extraordinarily good solutions added). … As good as this book is, it provides only a limited view of Nob's extraordinary output of puzzles. I'd like to end by mentioning a puzzle not included in this book that I believe to be among his very best.” (John J. Watkins, Mathematical Reviews, May, 2022)

“This is a collection of 200 mathematical puzzles, each solved by the editors, with careful explanations … . The intended audience ‘includes bright young children.’” (Victor V. Pambuccian, zbMATH 1465.00007, 2021)

• Edmonton, Canada

  Andy Liu

• Wayside, USA

  George Sicherman

• Tokyo, Japan

  Takayuki Yoshigahara

Andy Liu is an Emeritus Professor at the Department of Mathematical and Statistical Sciences, University of Alberta in Edmonton, Canada, where he obtained his Master’s degree in Number Theory in 1972, his PhD in Combinatorics in 1976, and a Professional Diploma in Elementary Education in the same year. His initial appointment was in 1980 and he retired in 2013. He was actively involved in mathematics competitions at all levels, including the International Mathematical Olympiad and the International Mathematics Tournament of the Towns. He also ran a mathematics circle for schoolchildren from 1981 to 2012, before handing it over to his successors. His informal interests include literature and history, mechanical puzzles and simulation board games.

George Sicherman is a computer programmer in New Jersey, originally from Buffalo, in New York State, USA.  He holds an M.A. in Mathematics and a Ph.D. in Computer Science from the University of Buffalo, having worked in industry till 2009. He has a large website about polyominoes and related figures and often writes computer programs to help other recreational mathematicians.  He has designed a variety of puzzles and is the inventor of Sicherman Dice.



Takayuki Yoshigahara is an engineer of an electronics company in Japan. His scientific/professional interests are computer vision and machine learning. His father Nobuyuki Yoshigahara is a great puzzle inventor, and Takayuki has inherited a fondness for solving problems, often using computer algorithms.

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