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## Mathematical Structures

The webpages collected here list information about classes of mathematical structures. The aim is to have a central place to check what properties are known about these structures.

These pages are currently still under construction. Knowledgeable readers are encouraged to add or correct information. To enable the edit button on each page, use the Login link (above) to log in or create an account.

Initially the main content concerns mostly first-order classes of relational structures and, more particularly, equationally defined classes of algebraic structures. If you are familiar with some of these classes of structures, feel free to add some relevant information and references by using the edit link on the respective page. Pages are written in DokuWiki syntax, but mathematical notation is in standard LaTeX. The previous versions of these pages are still available at http://math.chapman.edu/cgi-bin/structures.pl and http://math.chapman.edu/cgi-bin/structures . You can use this Sandbox page to try out editing (without worrying about deleting useful information).

Suggestions or comments? Just follow the link and edit the page.

**New:** Boldface links below display lists of finite algebras in a particular class (calculated locally in the browser).

Acknowledgements | Notation and terminology | Properties | Tools | Online books and lecture notes

Varieties | Quasivarieties | Universal classes | First-order classes | Second-order classes

Algebras | Logics | Syntax | Terms | Equations | Horn formulas | Universal formulas | First-order formulas

#### Alphabetical list of all classes

Trace: » index.html