20-XX
19 | 
Top | 
22 20-XX | 19 | Top | 22 |
| 20-00 | General reference works (handbooks, dictionaries, bibliographies, etc.) |
| 20-01 | Instructional exposition (textbooks, tutorial papers, etc.) |
| 20-02 | Research exposition (monographs, survey articles) |
| 20-03 | Historical (must also be assigned at least one classification number from Section 01) |
| 20-04 | Explicit machine computation and programs (not the theory of computation or programming) |
| 20-06 | Proceedings, conferences, collections, etc. |
| 20-99 | None of the above, but in this section. |
| 20Axx | Foundations |
| 20Bxx | Permutation groups |
| 20Cxx | Representation theory of groups [See also 19A22 (for representation rings and Burnside rings)] |
| 20Dxx | Abstract finite groups |
| 20Exx | Structure and classification of infinite or finite groups |
| 20Fxx | Special aspects of infinite or finite groups |
| 20Gxx | Linear algebraic groups (classical groups) {For arithmetic theory, see 11E57, 11H56; for geometric theory, see 14Lxx, 22Exx; for other methods in representation theory, see 15A30, 22E45, 22E46, 22E47, 22E50, 22E55} |
| 20Hxx | Other groups of matrices [See also 15A30] |
| 20Jxx | Connections with homological algebra and category theory |
| 20Kxx | Abelian groups |
| 20L05 | Groupoids (i.e. small categories in which all morphisms are isomorphisms) {For sets with a single binary operation, see 20N02; for topological groupoids, see 22A22, 58H05} |
| 20Mxx | Semigroups |
| 20Nxx | Other generalizations of groups |
| 20P05 | Probabilistic methods in group theory [See also 60Bxx] |