English
If a ⩿ b and b ⩿ c, then a ⩿ c (transitivity of the covering relation).
Русский
Если a ⩿ b и b ⩿ c, тогда a ⩿ c (транзитивность).
LaTeX
$$$a \\\\mathrel{\\\\trianglelefteq} b \\\\land b \\\\mathrel{\\\\trianglelefteq} c \\\\Rightarrow a \\\\mathrel{\\\\trianglelefteq} c.$$$
Lean4
theorem trans_wcovBy (hab : AntisymmRel (· ≤ ·) a b) (hbc : b ⩿ c) : a ⩿ c :=
⟨hab.1.trans hbc.le, fun _ had hdc => hbc.2 (hab.2.trans_lt had) hdc⟩