Keywords: Higman-Sims-19.svg Higman-Sims graph as an orthogonal projection from a subset of the Leech lattice emphasizing a rotational symmetry of order 11 There are 11 possible such projections if we require all 22 points connected to the center point to form a regular 22-gon around it graphe de Higman-Sims comme projection orthogonale d'un sous-ensemble du réseau de Leech mettant en évidence une symétrie rotationnelle d'ordre 11 Il y a 11 telles projections possibles si on impose aux 22 points reliés au point central de former un 22-gone régulier autour de lui own Gro-Tsen 2010-10-30 Higman-Sims Graph |