SSL Minutes for Tuesday, Nov. 18, 2003 Notes: Sam Lachterman Snacks: Martin Hock Hal will take notes on Thursday. Paul will bring snacks Thursday. Jim: Have we found out about posting sequences to the Online Encyclopedia of Integer Sequences? Paul: Sam has done so--you fill out a form and then the moderator decides what gets posted. Jim: A while back we found that for the sequence of matchings of the 2-by-2-by-n (cube) snake, every other term is a perfect square (and the ones which are not are twice a perfect square). Moreover, we showed that the weighted "version" is also a perfect square (or twice a square) for some natural weighting scheme of the edges. Has anyone looked into proving the positivty of the coefficients? That is, that they are counting something? (No). Jim: Well let's move on, if you all have moved on. Has anyone looked at the two articles which I sent in a prior e-mail about Markoff-like entities? That is, entities whose integer solutions can be found from a fundamental one? Entities of the form: ax^2+by^2+cz^2=dxyz for constants a,b,c,d Can we find a geometrical picture? [Jim goes to board] Given a triple (a,b,c) such that a