SSL Minutes for Tuesday, Nov. 4, 2003 Note-taker: Hal Snacks: Emilie Paul will take notes next time. Abby will bring snacks next time. Everyone seemed to be here except for Stephen, who was an hour late. We started in B107. Someone brought up graph.tcl. How to use it under Windows. First, get the newer version http://jamespropp.org/alt/graph.tcl Get TCL from ActiveState: http://www.activestate.com/Products/ASPN_Tcl/ To delete vertices, click both mouse buttons. The link http://jamespropp.org/SSL/private/Projects-2003 from http://jamespropp.org/SSL/private/ doesn't work. Jim will delete them. Maybe add a link to before.mws. Next time: Paul will take notes, and Abbie will bring snacks. We all got accounts at undergrad.math.wisc.edu cluster. I noticed that it was firewalled off. This has now been fixed. Summaries: Martin looked at the cube snake recurrence. To remind us, we had found that the recurrence was two known sequences interleaved. We want to find a nice bijection for them. (*) Carl is interested in that problem (*), but hasn't done much with it. John infected Carl with an unrelated math problem. He apologizes. John looked at face matching of cube snakes. Here is the question: "If a snake is heading in the x direction and bend into the y direction and then back to the x direction, does it have the same number of matchings as a cube that is heading in the x direction and bend into the y direction and then into the z direction?" John claims that the answer is yes for face matchings and no for edge matchings (using graph.tcl to find a counterexample). Paul wants to work on the bijection problem (ref *) in a group. He also studied the Laurent polynomials. He found a sequence of numbers (from coefficients of Laurent polynomials) that were not in the handbook. Should he submit them to the Handbook. Jim says to look into the procedure for that. Sam looked at (*), Also reading Itsara Article. We agree that Markoff snakes are a subset of snakes that, among other properties never bend left and immediately right. They are also symmetric under 180 degree rotation. He also looked at Somos sequences. Emilie solved the equations from the triangle system that Jim talked about last week. Hal talked about where to go with the Soddy Relation. Abby looked at the relationship between dominoes and cube snakes. She got half of the bijection (*). We break up and work on different things.