Recurrence 4 lookup certificate: B2 source bound

This is a checked coefficient-lookup shard for the fourth pseudo-division recurrence in the order-seven certificate.

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence4B2_coeff_high (n : ℕ) (h : 168 < n) : Polynomial.coeff remainder5Coefficient2 n = 0

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence4B2_natDegree_le : Polynomial.natDegree remainder5Coefficient2 ≤ 168