12 lines
336 B
Text
12 lines
336 B
Text
import hott.path tools.tactic
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open path tactic
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open path (rec_on)
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definition concat_whisker2 {A} {x y z : A} (p p' : x ≈ y) (q q' : y ≈ z) (a : p ≈ p') (b : q ≈ q') :
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(whiskerR a q) ⬝ (whiskerL p' b) ≈ (whiskerL p b) ⬝ (whiskerR a q') :=
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begin
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apply (rec_on b),
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apply (rec_on a),
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apply ((concat_1p _)⁻¹),
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end
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