Combinatorial species# Todo Short blurb about species Todo Proofread / point to the main classes rather than the modules? Introductory material# Enumeration of trees using generating functions Species, decomposable combinatorial classes Lazy Power Series# Streams or Infinite Arrays Series Order Lazy Power Series Generating Series Basic Species# Combinatorial Species Empty Species Recursive Species Characteristic Species Cycle Species Partition Species Permutation species Linear-order Species Set Species Subset Species Examples of Combinatorial Species Operations on Species# Sum species Product species Composition species Functorial composition species Miscellaneous# Species structures Miscellaneous Functions