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arXiv · 0802.2385

Essential variables and positions in terms

Slavcho Shtrakov
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Abstract

The paper deals with $Σ-$composition of terms, which allows us to extend the derivation rules in formal deduction of identities. The concept of essential variables and essential positions of terms with respect to a set of identities is a key step in the simplification of the process of formal deduction. $Σ-$composition of terms is defined as replacement between $Σ$-equal terms. This composition induces $ΣR-$deductively closed sets of identities. In analogy to balanced identities we introduce and investigate $Σ-$balanced identities for a given set of identities $Σ$.

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Slavcho Shtrakov. 2010-01-19. Essential variables and positions in terms. https://arxiv.org/abs/0802.2385

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