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Hironaka.Scheme.IdealSheaf.Order.MaxOrdAnti

The maximal order is antitone in the ideal sheaf #

[Kol07, Definition 47]: ord_x I ≥ r iff I_x ⊆ 𝔪_x^r, and max-ord I := max{ord_x I : x ∈ X}. A larger ideal sheaf has a smaller order at every point (ord_anti, Hironaka/Scheme/IdealSheaf/Order/Basic.lean), hence a smaller maximal order:

Used in the first step of the proof of [Kol07, Theorem 107] ([Kol07, 111]) in the form max-ord N(J) ≤ max-ord J for the nonmonomial part N(J) ⊇ J (Hironaka/Resolution/Algebraic/MarkedOrderReduction/Step1NonmonomialPart.lean, Hironaka/Resolution/Algebraic/MarkedOrderReduction/Clause3.lean, Hironaka/Resolution/Algebraic/MarkedOrderReduction/Step2Separation.lean).

The maximal order along a subset is antitone in the ideal sheaf — pointwise ord_anti under the supremum.

The maximal order is antitone in the ideal sheaf, I ≤ J → max-ord J ≤ max-ord I; in its use, max-ord N(J) ≤ max-ord J since J ⊆ N(J).