On automorphisms of a distance-regular graph with intersection array {39,36,22;1,2,18}

摘要

Prime divisors of orders of automorphisms and the fixedpoint subgraphs of automorphisms of prime orders are studied for ahypothetical distance-regular graph with intersection array f39; 36; 22; 1;2; 18g. Let G = Aut(??) is nonsolvable group, G= G=S(G) and T isthe socle of G. If ?? is vertex-symmetric then T = L M and L;M =Z5;A5;A6 or PSp(4; 3).