English
If ι is nonempty and ι is a singleton, the X variable set forms a transcendence basis for the polynomial ring in one variable over R.
Русский
Если ι непуст и единичен, множество переменных X образует базис трансцендентности для многочлена в одну переменную над R.
LaTeX
$$$ [Nonempty ι] [Subsingleton ι] : IsTranscendenceBasis R (fun _ => X)$$$
Lean4
theorem polynomial [Nonempty ι] [Subsingleton ι] : IsTranscendenceBasis R fun _ : ι ↦ (.X : Polynomial R) :=
by
nontriviality R
have := (nonempty_unique ι).some
refine
(isTranscendenceBasis_equiv (Equiv.equivPUnit.{_, 1} _).symm).mp <|
(MvPolynomial.pUnitAlgEquiv R).symm.isTranscendenceBasis_iff.mp ?_
convert IsTranscendenceBasis.mvPolynomial PUnit R
ext; simp