English
The composition of two equivariant additive monoid homomorphisms is again such a homomorphism.
Русский
Сложение двух эквариантных аддитивных моноид-гомоморфизмов снова даёт такой гомоморфизм.
LaTeX
$$$ g \\circ f : A \\to_{\\chi} C \\text{ is an equivariant additive monoid homomorphism}$$$
Lean4
/-- Composition of two equivariant additive monoid homomorphisms. -/
def comp (g : B →ₑ+[ψ] C) (f : A →ₑ+[φ] B) [κ : MonoidHom.CompTriple φ ψ χ] : A →ₑ+[χ] C :=
{ MulActionHom.comp (g : B →ₑ[ψ] C) (f : A →ₑ[φ] B), AddMonoidHom.comp (g : B →+ C) (f : A →+ B) with }