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Tree Automata Make Ordinal Theory Easy

Thierry Cachat

cs.GTarXiv:cs/0610166

Abstract

We give a new simple proof of the decidability of the First Order Theory of (omegaomegai,+) and the Monadic Second Order Theory of (omegai,<), improving the complexity in both cases. Our algorithm is based on tree automata and a new representation of (sets of) ordinals by (infinite) trees.

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