# An Adaptive Prefix-Assignment Technique for Symmetry Reduction

@article{Junttila2017AnAP, title={An Adaptive Prefix-Assignment Technique for Symmetry Reduction}, author={Tommi A. Junttila and Matti Karppa and Petteri Kaski and Jukka Kohonen}, journal={J. Symb. Comput.}, year={2017}, volume={99}, pages={21-49} }

This paper presents a technique for symmetry reduction that adaptively assigns a prefix of variables in a system of constraints so that the generated prefix-assignments are pairwise nonisomorphic under the action of the symmetry group of the system. The technique is based on McKay's canonical extension framework [J.~Algorithms 26 (1998), no.~2, 306--324]. Among key features of the technique are (i) adaptability---the prefix sequence can be user-prescribed and truncated for compatibility with…

## One Citation

### A Symmetry-Breaking Node Equivalence for Pruning the Search Space in Backtracking Algorithms

- Computer ScienceSymmetry
- 2019

A new equivalence on graphs is introduced, defined by its symmetry-breaking capability, in which the equivalence is used to prune the search tree and an optimization problem with the goal of finding an equivalence partition with the highest pruning potential is defined.

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