PROBLEM BOOKS IN MATHEMATICS

By KENNETH SANCHEZ

1 The Invariance Principle 1 2 Coloring Proofs 25 3 The Extremal Principle 39 4 The Box Principle 59 5 Enumerative Combinatorics 85 6 Number Theory 117 7 Inequalities 161 8 The Induction Principle 205 9 Sequences 221 10 Polynomials 245 11 Functional Equations 271 12 Geometry 289 13 Games 361 14 Further Strategies 373 References 397