Catalan Traffic and Integrals on the Grassmannians of Lines
arXiv:0704.2376 · doi:10.1016/j.disc.2007.03.085
Abstract
We prove that certain numbers occurring in a problem of paths enumeration, studied by Niederhausen (Catlan Traffic at the Beach, The Electronic Journal of Combinatorics, 9, (2002), 1--17), are top intersection numbers in the cohomology ring of the grassmannians of the lines in the complex projective (n+1)-space.
Excerpt from my Ph.D. Thesis; to appear on "Discrete Mathematics"