Mixed Four entry norm le envelope

import Mathlib.Analysis.CStarAlgebra.Matrix
import Mathlib.Analysis.Complex.Basic
import Mathlib.Analysis.Complex.Polynomial.Basic
import Mathlib.Data.Complex.Basic
import Mathlib.LinearAlgebra.Matrix.Determinant.Basic
import Mathlib.LinearAlgebra.Matrix.Permutation
import Mathlib.Tactic.FieldSimp
import Mathlib.Tactic.FinCases
import Mathlib.Tactic.Linarith
import Mathlib.Tactic.LinearCombination
import Mathlib.Tactic.NormNum
import Mathlib.Tactic.Ring
import Definitions.Def_D1Bound5_WeightedRowCertificate_Definitions

section
namespace D1Bound5















end D1Bound5

namespace D1Bound5


theorem _root_.D1Bound5.mixedFour_entry_norm_le_envelope
    (E : Matrix (Fin 4) (Fin 4) ℂ)
    (hdiag : ∀ i, E i i = 0)
    (hfirst : ∀ i j, i ≠ j → i = 0 ∨ j = 0 →
      ‖E i j‖ < (1 / 18 : ℝ))
    (hlater : ∀ i j, i ≠ j → ¬(i = 0 ∨ j = 0) →
      ‖E i j‖ < (1 / 64 : ℝ))
    (i j : Fin 4) :
    ‖E i j‖ ≤ mixedFourEnvelope i j := by sorry



end D1Bound5
end