Buffalo Soldier Sudoku Series
Einstein's Equation of Sudoku
Relativity, Logic, and the Limits of Human Reasoning
The fifth and culminating volume presents 80 maximum-difficulty Sudoku challenges for experienced solvers working through sustained, multi-step deduction, concentration, and careful reasoning.
Amazon retail shown in the July 2026 catalog: $12.99. Price and availability may change.
Who it is for
Built for practical use.
Independent solvers, families, libraries, recreation programs, waiting areas, and cognitive-engagement settings.
- Eighty themed Sudoku challenges
- Designed for sustained focus and logical reasoning
- Progressive series format
- 106-page paperback
- Published July 28, 2026
- Trim size: 7 × 0.24 × 10 inches
