Recurrence 2 lookup certificate: B3 source bound

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

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence2B3_coeff_high (n : ℕ) (h : 142 < n) : Polynomial.coeff remainder3Coefficient3 n = 0

theorem MazurTorsion.Kubert.OrderSevenBacktrackingCertificate.Internal.ResultantCertificate.recurrence2B3_natDegree_le : Polynomial.natDegree remainder3Coefficient3 ≤ 142