18 lines
440 B
Plaintext
18 lines
440 B
Plaintext
Semantics of FOL
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-- graph theory
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-- \Sigma \entails \alpha
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-- Lemma : two assignments agree on FV(\alpha) in a structure L,
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then M \entails \alpha under s_1
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iff
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M \entails \alpha under s_1
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-- Proof of lemma : terms, atomic formuals.
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-- Examples :
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-- L =(R(,))
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M1=(\nat, <)
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M2=(\nat, divides)
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M3=(pow(nat), \subset)
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formulas : R(x,y)
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: \exists x \forall y (R(x,y)).
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