18 lines
376 B
Text
18 lines
376 B
Text
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import standard
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using num
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namespace foo
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variable le : num → num → Bool
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axiom le_trans {a b c : num} : le a b → le b c → le a c
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calc_trans le_trans
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infix `≤`:50 := le
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end
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namespace foo
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theorem T {a b c d : num} : a ≤ b → b ≤ c → c ≤ d → a ≤ d
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:= assume H1 H2 H3,
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calc a ≤ b : H1
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... ≤ c : H2
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... ≤ d : H3
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end
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