MIT Combinatorics Seminar From dominoes to hexagons Dylan Thurston  (Harvard University) http://www.math.harvard.edu/~dpt/ Wednesday, September 29, 2004    4:15 pm    Room 2-338 ABSTRACT There is a natural generalization of domino tilings to tilings of a polygon by hexagons, or, dually, configurations of oriented curves that meet in triples. We show exactly when two such tilings can be connected by a series of moves analogous to the domino flip move. These triple-crossing diagrams have connections to Legendrian knots, planar algebras, and the octahedron recurrence.