In
graph theory, a branch of
mathematics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
, a periodic graph with respect to an operator ''F'' on graphs is one for which there exists an integer ''n'' > 0 such that ''F
n''(''G'') is
isomorphic
In mathematics, an isomorphism is a structure-preserving mapping between two structures of the same type that can be reversed by an inverse mapping. Two mathematical structures are isomorphic if an isomorphism exists between them. The word is ...
to ''G''. For example, every graph is periodic with respect to the
complementation operator, whereas only
complete graphs are periodic with respect to the operator that assigns to each graph the complete graph on the same vertices. Periodicity is one of many properties of graph operators, the central topic in graph dynamics.
References
Graph invariants
Graph operations
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