40 Topology
41 Point set topology. General topological spaces
42 Topological analysis. Theory of functions on a topological space
43 Algebraic and combinatorial topology. Homology. Co-Homology. Homotopy. Co-Homotopy. Fibre spaces. Differential topology
44 Topological groups. Continuous groups. Lie groups. Compact groups. Continuous transformations groups. Automorphic representations
45 Manifolds. Bundles. Differential topology. Differential manifolds. Catastrophe. Low dimensional topology. Global analysis
46 Graph theory. Weaves. Design theory
See also: 81.2 Combinatorics
47 Dimension theory
48 Knots
49 Dynamical systems. Topological dynamics. Ergodic theory. Chaos. Complex systems