cases h1 with
| inl h1 =>
  use f.prod
  rw [h1, hf, Multiset.prod_nsmul]
| inr h1 =>
  use -f.prod
  rw [h1, hf, Multiset.prod_nsmul, Odd.neg_pow]
  norm_num
case intro.intro
a : ℤ√(-3)
r : ℤ
hcoprime : IsCoprime a.re a.im
hcube : r ^ 3 = Zsqrtd.norm a
f : Multiset (ℤ√(-3))
hf : factorization' hcoprime = 3 • f
h1 : a = Multiset.prod (factorization' hcoprime) ∨ a = -Multiset.prod (factorization' hcoprime)
⊢ ∃ p, a = p ^ 3
no goals