English
Composition of bialg homomorphisms is again a bialg homomorphism, combining both coalgebra and algebra structures.
Русский
Композитный гомоморфизм биналгомов снова гомоморфизм биналгомов, сохраняющий обе структуры.
LaTeX
$$$\\mathrm{comp}(\\phi_1 : B \\to_{R}^{\\!c} C, \\; \\phi_2 : A \\to_{R}^{\\!c} B) \\in \\mathrm{BialgHom}(R,A,C)$$$
Lean4
/-- Composition of bialgebra homomorphisms. -/
@[simps!]
def comp (φ₁ : B →ₐc[R] C) (φ₂ : A →ₐc[R] B) : A →ₐc[R] C :=
{ (φ₁ : B →ₗc[R] C).comp (φ₂ : A →ₗc[R] B), (φ₁ : B →ₐ[R] C).comp (φ₂ : A →ₐ[R] B) with }