Skip to main content
8 events
when toggle format what by license comment
May 3, 2017 at 20:07 comment added Ira Gessel A reference for Fedor Petrov's comment is Richard P. Stanley, Two poset polytopes, Discrete Comput. Geom. 1 (1986), no. 1, 9–23, dedekind.mit.edu/~rstan/pubs/pubfiles/66.pdf.
May 2, 2017 at 11:55 comment added T. Amdeberhan @ZurabSilagadze: This is cool. I wish we can give a direct transformation rule from $\square$ to $\Delta$ shapes, because your idea goes through $\square$ to $\delta$ and then followed by algebraic comparison of the volumes of $\Delta$ and $\delta$.
May 2, 2017 at 10:44 comment added Zurab Silagadze Yes, indeed if we mean the volume of the zigzag chain polytope (see, for example arxiv.org/abs/0912.4240). However, $\delta_n$ is not quite a zigzag chain polytope because of $n_n+u_1\le 1$ extra condition.
May 2, 2017 at 10:36 history edited Zurab Silagadze CC BY-SA 3.0
Some extra text added
May 2, 2017 at 5:27 comment added Fedor Petrov It is well known that the volume of $\{u_i\geq 0, u_i+u_{i+1}\leqslant 1\}$ equals Euler number divided by factorial. Though I can not give a reference immediately.
May 2, 2017 at 5:23 history edited Zurab Silagadze CC BY-SA 3.0
typos corrected
May 2, 2017 at 5:17 history edited Zurab Silagadze CC BY-SA 3.0
some corrections
May 2, 2017 at 5:09 history answered Zurab Silagadze CC BY-SA 3.0