ARTICLES
The Faces of the Tri-Hexaflexagon
by Peter Hilton, Jean Pedersen, and Hans Walser
Centers of Triangles of Fixed Center: Adventures in Undergraduate Research
by William Mueller
A Family Portrait of Primes--A Case Study in Discrimination
by Shailesh A. Shirali
Mathematics Teachers
by JoAnne Growney
Halley's Comment--Projectiles With Linear Resistance
by C. W. Groetsch and Barry Cipra
Carl B. Allendoerfer Awards--1997
NOTES
Scheduling a Bridge Club Using a Genetic Algorithm
by R. J. Simpson
Scheduling a Bridge Club by Tabu Search
by Luis B. Morales
Arg
by John A. Baker and Willem Sluis
Math Bite
by Doron Zeilberger
Understanding the Extra Power of the Newton-Cotes Formula for Even Degree
by Kenneth J. Supowit
Proof Without Words: Sums of Consecutive Positive Integers
by C. L. Frenzen
The Volume of a Cone, Without Calculus
by M. Hirschhorn
A Basis for the Intersection of Subspaces
by Kung-Wei Yang
PROBLEMS
Proposals 1529-1533
Quickies 868-870
Solutions 1504-1508
Answers 868-870
REVIEWS
NEWS AND LETTERS
The Root and Ratio Tests Revisited