All problems © Copyright 1998 Stan Wagon. Reproduced with permission.

- Problem 865: The Opaque Square
- Problem 864: The Ten Implications
- Problem 863: Cut Twice To Make a Square
- Problem 862: A Programming Challenge
- Problem 861: The Bald Traveling Salesman
- Problem 860: Pablito's Solitaire
- Problem 859: Four Non-Fours
- Problem 858: Median Triangles
- Problem 857: An Elusive Quadratic
- Problem 856: A Tiling from Ell
- Problem 855: Dizzying Triangles
- Interlude: The Doomed Lemming
- Problem 854: A Circular Balancing Act
- Problem 853: A Nonstandard Coloring of a Checkerboard
- Problem 852: Symmetrical Triplets

Please don't ask us for answers!Solutions for almost every problem are posted to the mailing list for almost every problem, but at Professor Wagon's request we do not reproduce them here. If you can't sleep without knowing the answer to one of these problems, please contact Professor Wagon at wagon@macalester.edu.

1 May 2000