Imo Problems, Theorems, And Methods: Combinatorics (Mathematical Olympiad Series)
Sieve Methods (Dover Books on Mathematics)
LARGE SUDOKU: Large Print Hard Sudoku | Cognitive Boosting Puzzles
Combinatorial Optimization: Theory and Algorithms (Algorithms and Combinatorics Book 21)
Graph Theory and Its Applications (Textbooks in Mathematics)
Handbook of Applied Cryptography (Discrete Mathematics and Its Applications)
The Ultimate Hidato Puzzle Book for Adults: 500 Logic Puzzles to Reduce Brain Age Volume 1
Mathematics of Tabletop Games (AK Peters/CRC Recreational Mathematics Series)