Bennett Cleared Matrix det remove last
ProvedD1Bound5.bennettClearedMatrix_det_remove_lastdiophantine-tuplesnumber-theory
Exact determinant reduction at the removed node. Both directions of every new node difference are retained, so this identity contains its full sign.
Preamble
import Lean.Elab.Tactic.Omega import Mathlib.Algebra.BigOperators.Fin import Mathlib.Algebra.CharZero.Infinite import Mathlib.Algebra.Polynomial.BigOperators import Mathlib.Algebra.Polynomial.Degree.Operations import Mathlib.Algebra.Polynomial.Div import Mathlib.Algebra.Polynomial.PartialFractions import Mathlib.Algebra.Polynomial.RingDivision import Mathlib.Algebra.Polynomial.Roots import Mathlib.LinearAlgebra.Matrix.Polynomial import Mathlib.RingTheory.PowerSeries.Binomial import Mathlib.RingTheory.PowerSeries.Trunc import Mathlib.Tactic.Ring import Definitions.Def_D1Bound5_BennettDeterminantConstant_Definitions
Formal statement
section
open Finset
namespace D1Bound5
variable {F : Type*} [Field F] [CharZero F]
theorem _root_.D1Bound5.bennettClearedMatrix_det_remove_last
(n : ℕ) (a : Fin (n + 1) → F) (ha : Function.Injective a)
(k : ℕ) (hk : 1 ≤ k) (ν : F) :
(bennettClearedMatrix a k ν).det.eval (-a (Fin.last n)) =
Ring.choose ((k : F) + ν) k *
(∏ j : Fin n, ((a (Fin.last n) - a j.castSucc)⁻¹) ^ k) *
(∏ j : Fin n, ((a j.castSucc - a (Fin.last n))⁻¹) ^ k) *
(bennettClearedMatrix (fun j : Fin n ↦ a j.castSucc) k
(ν - (k : F))).det.eval (-a (Fin.last n)) := by sorry
end D1Bound5
end
Source
D1Bound5/BennettNodeRemoval.lean, lines 41-99, SHA-256 744b0d9ca6cef7f147ff8e1fb3ed54499f22a4c9c12ff289d69e5603296721b1. Project: https://github.com/tomislav-math/d1-bound5-lean