16 lines
413 B
Text
16 lines
413 B
Text
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inductive formula
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| eqf : nat → nat → formula
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| impf : formula → formula → formula
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namespace formula
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definition denote : formula → Prop
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| (eqf n1 n2) := n1 = n2
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| (impf f1 f2) := denote f1 → denote f2
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theorem denote_eqf (n1 n2 : nat) : denote (eqf n1 n2) = (n1 = n2) :=
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rfl
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theorem denote_impf (f1 f2 : formula) : denote (impf f1 f2) = (denote f1 → denote f2) :=
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rfl
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end formula
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