Theorem: C_p_pow_dvd_bind₁_rename_wittPolynomial_sub_sum
File: Mathlib/RingTheory/WittVector/StructurePolynomial.lean

Proof steps:
state_before: p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH : ∀ m < n, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
⊢ C ↑(p ^ n) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ n)) Φ -
      ∑ i ∈ Finset.range n, C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n - i)
state_after: case zero
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
IH : ∀ m < 0, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
⊢ C ↑(p ^ 0) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ 0)) Φ -
      ∑ i ∈ Finset.range 0, C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (0 - i)

case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
tactic: cases' n with n
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun b => (rename fun i => (b, i)) ((expand p) (W_ ℤ n))) Φ =
    (bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n)
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
tactic: have key := bind₁_rename_expand_wittPolynomial Φ n IH
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun b => (rename fun i => (b, i)) ((expand p) (W_ ℤ n))) Φ =
    (bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n)
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun b => (rename fun i => (b, i)) ((expand p) (W_ ℤ n))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
tactic: apply_fun map (Int.castRingHom (ZMod (p ^ (n + 1)))) at key
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun b => (rename fun i => (b, i)) ((expand p) (W_ ℤ n))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
tactic: conv_lhs at key => simp only [map_bind₁, map_rename, map_expand, map_wittPolynomial]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ C ↑(p ^ (n + 1)) ∣
    (bind₁ fun b => (rename fun i => (b, i)) (W_ ℤ (n + 1))) Φ -
      ∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i)
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ (bind₁ fun i => (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((rename fun i_1 => (i, i_1)) (W_ ℤ (n + 1))))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
tactic: rw [C_dvd_iff_zmod, RingHom.map_sub, sub_eq_zero, map_bind₁]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ (bind₁ fun i => (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((rename fun i_1 => (i, i_1)) (W_ ℤ (n + 1))))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
tactic: simp only [map_rename, map_wittPolynomial, wittPolynomial_zmod_self]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
tactic: rw [key]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
IH :
  ∀ m < n + 1, (map (Int.castRingHom ℚ)) (wittStructureInt p Φ m) = wittStructureRat p ((map (Int.castRingHom ℚ)) Φ) m
key :
  (bind₁ fun i => (rename fun i_1 => (i, i_1)) ((expand p) (W_ (ZMod (p ^ (n + 1))) n)))
      ((map (Int.castRingHom (ZMod (p ^ (n + 1))))) Φ) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n))
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
tactic: clear key IH
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) ((bind₁ fun i => (expand p) (wittStructureInt p Φ i)) (W_ ℤ n)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1)))))
      (∑ i ∈ Finset.range (n + 1), C (↑p ^ i) * wittStructureInt p Φ i ^ p ^ (n + 1 - i))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
⊢ ∀ x ∈ Finset.range (n + 1),
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ x * (expand p) (wittStructureInt p Φ x) ^ p ^ (n - x)) =
      (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ x) * wittStructureInt p Φ x ^ p ^ (n + 1 - x))
tactic: rw [bind₁, aeval_wittPolynomial, map_sum, map_sum, Finset.sum_congr rfl]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n : ℕ
⊢ ∀ x ∈ Finset.range (n + 1),
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ x * (expand p) (wittStructureInt p Φ x) ^ p ^ (n - x)) =
      (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ x) * wittStructureInt p Φ x ^ p ^ (n + 1 - x))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ∈ Finset.range (n + 1)
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ k * (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ k) * wittStructureInt p Φ k ^ p ^ (n + 1 - k))
tactic: intro k hk
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ∈ Finset.range (n + 1)
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ k * (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ k) * wittStructureInt p Φ k ^ p ^ (n + 1 - k))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ k * (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ k) * wittStructureInt p Φ k ^ p ^ (n + 1 - k))
tactic: rw [Finset.mem_range, Nat.lt_succ_iff] at hk
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
⊢ (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (↑p ^ k * (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k)) =
    (map (Int.castRingHom (ZMod (p ^ (n + 1))))) (C (↑p ^ k) * wittStructureInt p Φ k ^ p ^ (n + 1 - k))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
⊢ ↑(p ^ (n + 1)) ∣
    ↑(p ^ k) * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
tactic: rw [← sub_eq_zero, ← RingHom.map_sub, ← C_dvd_iff_zmod, C_eq_coe_nat, ← Nat.cast_pow,
    ← Nat.cast_pow, C_eq_coe_nat, ← mul_sub]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
⊢ ↑(p ^ (n + 1)) ∣
    ↑(p ^ k) * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑(p ^ (n + 1)) ∣
    ↑(p ^ k) * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
tactic: have : p ^ (n + 1) = p ^ k * p ^ (n - k + 1) := by
    rw [← pow_add, ← add_assoc]; congr 2; rw [add_comm, ← tsub_eq_iff_eq_add_of_le hk]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑(p ^ (n + 1)) ∣
    ↑(p ^ k) * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑(p ^ k * p ^ (n - k + 1)) ∣
    ↑(p ^ k) * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
tactic: rw [this]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑(p ^ k * p ^ (n - k + 1)) ∣
    ↑(p ^ k) * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ k * ↑p ^ (n - k + 1) ∣
    ↑p ^ k * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
tactic: rw [Nat.cast_mul, Nat.cast_pow, Nat.cast_pow]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ k * ↑p ^ (n - k + 1) ∣
    ↑p ^ k * ((expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ (n - k + 1) ∣ (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k)
tactic: apply mul_dvd_mul_left ((p : MvPolynomial (idx × ℕ) ℤ) ^ k)
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ (n - k + 1) ∣ (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ p ^ (n + 1 - k)
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ (n - k + 1) ∣ (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ (p * p ^ (n - k))
tactic: rw [show p ^ (n + 1 - k) = p * p ^ (n - k) by rw [← pow_succ', ← tsub_add_eq_add_tsub hk]]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ (n - k + 1) ∣ (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - wittStructureInt p Φ k ^ (p * p ^ (n - k))
state_after: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ (n - k + 1) ∣ (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - (wittStructureInt p Φ k ^ p) ^ p ^ (n - k)
tactic: rw [pow_mul]
state_before: case succ
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ^ (n - k + 1) ∣ (expand p) (wittStructureInt p Φ k) ^ p ^ (n - k) - (wittStructureInt p Φ k ^ p) ^ p ^ (n - k)
state_after: case succ.h
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ∣ (expand p) (wittStructureInt p Φ k) - wittStructureInt p Φ k ^ p
tactic: apply dvd_sub_pow_of_dvd_sub
state_before: case succ.h
p : ℕ
R : Type u_1
idx : Type u_2
inst✝ : CommRing R
hp : Fact (Nat.Prime p)
Φ : MvPolynomial idx ℤ
n k : ℕ
hk : k ≤ n
this : p ^ (n + 1) = p ^ k * p ^ (n - k + 1)
⊢ ↑p ∣ (expand p) (wittStructureInt p Φ k) - wittStructureInt p Φ k ^ p
state_after: no goals
tactic: rw [← C_eq_coe_nat, C_dvd_iff_zmod, RingHom.map_sub, sub_eq_zero, map_expand, RingHom.map_pow,
    MvPolynomial.expand_zmod]