# On Canonical Forms of Complete Problems via First-order Projections

@article{Borges2007OnCF, title={On Canonical Forms of Complete Problems via First-order Projections}, author={Nerio Borges and Blai Bonet}, journal={ArXiv}, year={2007}, volume={abs/0706.3412} }

The class of problems complete for NP via first-order reductions is known to be characterized by existential second-order sentences of a fixed form. All such sentences are built around the so-called generalized IS-form of the sentence that defines IndependentSet. This result can also be understood as that every sentence that defines a NP-complete problem P can be decomposed in two disjuncts such that the first one characterizes a fragment of P as hard as IndependentSet and the second the rest…

## 3 Citations

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