HvdH machine lemma CR.out_cost (Cost of the key generation (namespace `NLogN.CR`))
ProvedNLogN.CR.out_costThe following holds (Lean statement, in the scope of module NLogN.HCrKeyCost):
theorem NLogN.CR.out_cost (s0 : IState HS) (s : List ℕ) (hs : ∀ x ∈ s, 0 < x) (Rst LP T0 LK L4 : List Item)
(hK : s0.G kKR = .int s.length :: LK) (h4 : s0.G kK4 = .int ((4 * s.length : ℕ) : ℤ) :: L4)
(N k : ℕ) (B : ℕ) (hB : 2 * s.prod + 4 * s.length + 1 < 2 ^ B) :
outBody.cost (withCtr kC1 s0 N k (keySt s0 s Rst LP T0 k)) ≤
(s.length + 1) * 210000 * (B + 2)
Context. The lemma belongs to the part Cost of the key generation (namespace NLogN.CR).
Formalization Note. This is a lemma of the Lean development NLogN, a multitape-Turing-machine implementation of the Harvey–van der Hoeven integer multiplication algorithm, used in the proof of NLogN.FIN.theorem_1_1_nlogn : IntMul.MulTimeBound fun n => n * Real.log n. All names refer to the definition bundles IntMul_HvdH_M_Defs1–IntMul_HvdH_M_Defs8 (namespace NLogN), built on the platform model Def_IntMul_MultitapeModel and the published reference Def_IntMul_HvdH_MachineRef. The machine layer: IState HS is a state of 64 item stacks; RM programs have a semantics p.run s, a definedness predicate p.ok M s and a cost p.cost M s relative to a multiplication spec M : MulSpec; zsz z is the bit length of .
-- Harvey–van der Hoeven multitape-TM development (NLogN), generated by skeleton subtraction. import Definitions.Def_IntMul_HvdH_M_Defs8 set_option autoImplicit false set_option relaxedAutoImplicit false set_option maxHeartbeats 1000000 set_option linter.unusedSimpArgs false set_option linter.unusedVariables false open NLogN open NLogN.CR open IntMul IntMul.HvdH IntMul.HvdH.Ref RS
theorem NLogN.CR.out_cost (s0 : IState HS) (s : List ℕ) (hs : ∀ x ∈ s, 0 < x) (Rst LP T0 LK L4 : List Item)
(hK : s0.G kKR = .int s.length :: LK) (h4 : s0.G kK4 = .int ((4 * s.length : ℕ) : ℤ) :: L4)
(N k : ℕ) (B : ℕ) (hB : 2 * s.prod + 4 * s.length + 1 < 2 ^ B) :
outBody.cost (withCtr kC1 s0 N k (keySt s0 s Rst LP T0 k)) ≤
(s.length + 1) * 210000 * (B + 2) := by sorry