Definitions bundle OAIQ035K045 of the split of OpenAI, The approximation threshold for metric k-median (result family 125)
DefinitionOAIQ035K045A definitions bundle of the split of OpenAI's proof of OAI.MetricKMedian.main_finite_work, carved from OpenAI's openai/math development (OpenAI, The approximation threshold for metric k-median (result family 125), OpenAI Math Release, September 24, 2026, result family 125, github.com/openai/math at commit adc7f12, Apache License 2.0) and ported to Lean 4.33.1 and Mathlib 0df444a. The declarations and their proofs are OpenAI's.
Contents. It holds 4 declarations of OpenAI's Lean: 3 definitions and 1 theorem. The definitions and types are OAI.MetricKMedian.ScalarTransfer.stdK, OAI.MetricKMedian.SparseIntegerLaw.expectation, OAI.MetricKMedian.Taper.physicalGraphData.
Sources. They come from these modules of lean/OAI/Combinatorics/KMedian, in whole or in part: KMedian_Analysis_NormalizedTransfer, KMedian_Rounding_RationalPhysicalGraph, KMedian_Rounding_RationalTaperData, KMedian_Sparse_SparseRealExpectation.
Imports. It imports the bundles OAIQ035K029, OAIQ035K035, OAIQ035K036 and OAIQ035K037 of this split.
Imported by (directly, in this split): the statements OAI.MetricKMedian.FixedBatch.RationalParameters.completed_expectation, OAI.MetricKMedian.RationalPhysicalKernel.histories_count_tail, OAI.MetricKMedian.RationalPhysicalKernel.histories_drift, OAI.MetricKMedian.RationalPhysicalKernel.histories_survival, OAI.MetricKMedian.RationalPhysicalKernel.step_drift, OAI.MetricKMedian.RationalPhysicalKernel.step_survival, OAI.MetricKMedian.SparseHistories.accumulated_drift_up_to, OAI.MetricKMedian.SparseHistories.count_tail_up_to, OAI.MetricKMedian.SparseHistories.history_contraction and OAI.MetricKMedian.Taper.physical_sparse_graph; the proofs of OAI.MetricKMedian.FiniteComparison.actual_scalar_bounds, OAI.MetricKMedian.FixedBatch.RationalParameters.completed_expectation, OAI.MetricKMedian.FixedBatch.RationalParameters.selectCompleted_spec, OAI.MetricKMedian.RationalPhysicalKernel.graph_data, OAI.MetricKMedian.RationalPhysicalKernel.graph_data_all, OAI.MetricKMedian.RationalPhysicalKernel.histories_count_tail, OAI.MetricKMedian.RationalPhysicalKernel.histories_drift, OAI.MetricKMedian.RationalPhysicalKernel.histories_survival, OAI.MetricKMedian.RationalPhysicalKernel.step_drift, OAI.MetricKMedian.RationalPhysicalKernel.step_survival, OAI.MetricKMedian.SparseEnumeratedBatch.marginal_error, OAI.MetricKMedian.SparseEnumeratedBatch.marginal_le, OAI.MetricKMedian.SparseEnumeratedBatch.marginal_lower, OAI.MetricKMedian.SparseEnumeratedBatch.pair_le, OAI.MetricKMedian.SparseEnumeratedBatch.prob_eq, OAI.MetricKMedian.SparseEnumeratedBernoulli.conditional_count_tail, OAI.MetricKMedian.SparseHistories.accumulated_drift_up_to, OAI.MetricKMedian.SparseHistories.count_tail_up_to, OAI.MetricKMedian.SparseHistories.history_contraction and OAI.MetricKMedian.Taper.physical_sparse_graph.
import Mathlib
import Definitions.Def_OAIQ035K029
import Definitions.Def_OAIQ035K035
import Definitions.Def_OAIQ035K036
import Definitions.Def_OAIQ035K037
section
-- module Solutions.OAIQ035_KM.KMedian_Analysis_NormalizedTransfer
set_option linter.all false
set_option linter.unusedVariables false
set_option linter.unusedTactic false
set_option linter.unreachableTactic false
namespace OAI
section
section
namespace MetricKMedian.ScalarTransfer
noncomputable def stdK (p k x w r : ℝ) (s : Bool) : ℝ :=
N p k s-stdB p x w s*r+(8/5)*p*w^2
end MetricKMedian.ScalarTransfer
end
end
end OAI
end
section
-- module Solutions.OAIQ035_KM.KMedian_Rounding_RationalTaperData
set_option linter.all false
set_option linter.unusedVariables false
set_option linter.unusedTactic false
set_option linter.unreachableTactic false
namespace OAI
section
section
namespace MetricKMedian.Taper
open Finset
variable {I : Type*} [Fintype I] [LinearOrder I]
theorem rational_data (g P : ℚ) (d : I → ℚ) (own : Finset I) (Δ : ℕ)
(hg : 0 < (g:ℝ)) (hunit : (g:ℝ)*(Δ:ℝ)=1)
(hP : 0 < (P:ℝ)) (hP1 : (P:ℝ) ≤ 1/2)
(hd : ∀ i, 0 ≤ d i) (htotal : 1 ≤ ∑ _i : I, (g:ℝ))
(hown : ∀ i ∈ own, d i=0) (howncard : own.card ≤ Δ) :
let N := rationalRadius g P d
let q := sourceMarginals g P d own Δ
0 ≤ N ∧ (∀ i, 0 ≤ q i) ∧ (∀ i, q i ≤ 1) ∧
(∑ i, g*q i=1) ∧ (∑ i, q i=Δ) ∧ (∀ i ∈ own, q i=1) ∧
(∀ i, q i < 1 → N*(1-P*q i) ≤ d i) ∧
(∀ i, 0 < q i → d i ≤ N*(1-P*q i)) ∧
(∀ R : ℝ, 0 < R → 1 ≤ mass g P (fun i => (d i:ℝ)) (1/R) → (N:ℝ) ≤ R) := by
by_cases hc : 1 ≤ rationalColocatedMass g d
· have hcR : 1 ≤ colocatedMass g (fun i => (d i:ℝ)) := by
rw [← cast_rationalColocatedMass]
exact_mod_cast hc
obtain ⟨hq0,hq1,hs,hn,ho,hz⟩ := zero_data g d own Δ hg hunit hcR hown howncard
dsimp only
simp only [rationalRadius,sourceMarginals,ite_eq_left hc]
refine ⟨le_refl _,hq0,hq1,hs,hn,ho,?_,?_,?_⟩
· intro i _; simpa only [zero_mul] using hd i
· intro i hi; simp only [hz i hi,zero_mul,le_refl]
· intro R hR _; simpa only [Rat.cast_zero] using hR.le
· have hcR : colocatedMass g (fun i => (d i:ℝ)) < 1 := by
rw [← cast_rationalColocatedMass]
exact_mod_cast (lt_of_not_ge hc)
obtain ⟨hN,hq0,hq1,hs,hn,ho,hl,hu,hr⟩ := positive_data g P d Δ hg hunit hP hP1 hd htotal hcR
dsimp only
simp only [rationalRadius,sourceMarginals,ite_eq_right hc]
exact ⟨hN.le,hq0,hq1,hs,hn,fun i hi => ho i (hown i hi),hl,hu,hr⟩
end MetricKMedian.Taper
end
end
end OAI
end
section
-- module Solutions.OAIQ035_KM.KMedian_Rounding_RationalPhysicalGraph
set_option linter.all false
set_option linter.unusedVariables false
set_option linter.unusedTactic false
set_option linter.unreachableTactic false
namespace OAI
section
section
namespace MetricKMedian.Taper
open Finset
variable {I : Type} [LinearOrder I] [Fintype I] {n : ℕ} {X : Type*} [PseudoMetricSpace X]
noncomputable def physicalGraphData (Δ : ℕ) (g P : ℚ) (d : I → I → ℚ)
(location : I → X) (own : I → Finset (I))
(hg : 0 < (g:ℝ)) (hunit : (g:ℝ)*(Δ:ℝ)=1)
(hP : 0 < (P:ℝ)) (hP1 : (P:ℝ) ≤ 1/2)
(hd : ∀ i h, 0 ≤ d i h) (hdist : ∀ i h, dist (location i) (location h)=(d i h:ℝ))
(htotal : 1 ≤ ∑ _i : I, (g:ℝ))
(hown : ∀ i h, h∈own i → d i h=0) (howncard : ∀ i, (own i).card ≤ Δ) :
GraphData Δ (g:ℝ) (P:ℝ) location own where
radius i := (rationalRadius g P (d i):ℝ)
marginal h i := (sourceMarginals g P (d i) (own i) Δ h:ℝ)
radius_nonneg i := by
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).1
marginal_nonneg h i := by
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.1 h
marginal_le_one h i := by
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.2.1 h
incoming_mass i := by
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.2.2.1
incoming_count i := by
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.2.2.2.1
own_certain i h he := by
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.2.2.2.2.1 h he
lower h i he := by
rw [hdist]
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.2.2.2.2.2.1 h (by exact_mod_cast he)
upper h i he := by
rw [hdist]
exact_mod_cast (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.2.2.2.2.2.2.1 h (by exact_mod_cast he)
minimal i R hR he := by
simp only [hdist] at he
exact (rational_data g P (d i) (own i) Δ hg hunit hP hP1 (hd i) htotal (hown i) (howncard i)).2.2.2.2.2.2.2.2 R hR he
end MetricKMedian.Taper
end
end
end OAI
end
section
-- module Solutions.OAIQ035_KM.KMedian_Sparse_SparseRealExpectation
set_option linter.all false
set_option linter.unusedVariables false
set_option linter.unusedTactic false
set_option linter.unreachableTactic false
namespace OAI
namespace MetricKMedian.SparseIntegerLaw
open Finset
variable {α β : Type}
noncomputable def expectation (μ : SparseIntegerLaw α) (f : α → ℝ) : ℝ :=
μ.realIndex.expect (fun i => f μ.states[i.val])
end MetricKMedian.SparseIntegerLaw
end OAI
end