Sphere Packing, Lewis Carroll, and Reversi

For 25 of his 90 years, Martin Gardner wrote 'Mathematical Games and Recreations,' a monthly column for Scientific American magazine. These columns have inspired hundreds of thousands of readers to delve more deeply into the large world of mathematics. He has also made significant contributions to magic, philosophy, debunking pseudoscience, and children's literature. He has produced more than 60 books, including many best sellers, most of which are still in print. His Annotated Alice has sold more than a million copies. He continues to write a regular column for the Skeptical Inquirer magazine.

1. The binary system; 2. Group theory and braids; 3. Eight problems; 4. The games and puzzles of Lewis Carroll; 5. Paper cutting; 6. Board games; 7. Sphere packing; 8. The transcendental number Pi; 9. Victor Eigen, mathemagician; 10. The four-color map theorem; 11. Mr. Apollinax visits New York; 12. Nine problems; 13. Polyominoes and fault-free rectangles; 14. Euler's spoilers: the discovery of an Order-10 Graeco-Latin square; 15. The ellipse; 16. The 24 color squares and the 30 color cubes; 17. H. S. M. Coxeter; 18. Bridg-it and other games; 19. Nine more problems; 20. The calculus of finite differences.