English
There is a bound on the number of algebra homomorphisms from V to W in terms of finrank(W, V→_L V).
Русский
Число алгебраических гомоморфизмов ограничено по финрэнку пространства линейных отображений.
LaTeX
$$$|V \\to_K W| \\le \\operatorname{finrank}_K(W, V \\to_L[K] W)$$$
Lean4
theorem cardinalMk_algHom (K : Type u) (V : Type v) (W : Type w) [Field K] [Ring V] [Algebra K V]
[FiniteDimensional K V] [Field W] [Algebra K W] : Cardinal.mk (V →ₐ[K] W) ≤ finrank W (V →ₗ[K] W) :=
(linearIndependent_toLinearMap K V W).cardinalMk_le_finrank