15 lines
254 B
Text
15 lines
254 B
Text
import tactic.
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infixl 50 => : implies
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variables a b c d e : Bool.
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axiom H1 : a → b.
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axiom H2 : b = c.
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axiom H3 : c → d.
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axiom H4 : d = e.
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theorem T : a → e
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:= calc a => b : H1
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... = c : H2
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... => d : H3
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... = e : H4.
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