# A Characterization of Individualization-Refinement Trees

@article{Anders2021ACO, title={A Characterization of Individualization-Refinement Trees}, author={Markus Anders and Jendrik Brachter and Pascal Schweitzer}, journal={ArXiv}, year={2021}, volume={abs/2109.07302} }

Individualization-Refinement (IR) algorithms form the standard method and currently the only practical method for symmetry computations of graphs and combinatorial objects in general. Through backtracking, on each graph an IR-algorithm implicitly creates an IR-tree whose order is the determining factor of the running time of the algorithm. We give a precise and constructive characterization which trees are IR-trees. This characterization is applicable both when the tree is regarded as an… Expand

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