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Chebyshev Certificates

LeanCert includes specialized certificate engines for finite Chebyshev function bounds. These engines use computable rational upper/lower envelopes for logarithmic summands, then expose Golden Theorems that turn successful boolean checks into real-number bounds.

Imports

import LeanCert.Engine.Chebyshev.Psi
import LeanCert.Engine.Chebyshev.Theta

or use the aggregate import:

import LeanCert

Psi Bounds

LeanCert.Engine.Chebyshev.Psi certifies upper bounds for the second Chebyshev function ψ.

Core checkers:

checkPsiLeMulWith (N : Nat) (slope : ℚ) (depth : Nat)
checkAllPsiLeMulWith (bound : Nat) (slope : ℚ) (depth : Nat)
Golden Theorems:

#check verify_psi_le_mul
Real-variable form:

#check verify_all_psi_le_mul_real

Theta Bounds

LeanCert.Engine.Chebyshev.Theta certifies upper, absolute-error, and relative-error bounds for the first Chebyshev function θ.

Core checkers:

checkThetaLeMulWith
checkAllThetaLeMulWith
checkThetaAbsError
checkAllThetaAbsError
checkThetaRelError
checkAllThetaRelError
checkThetaRelErrorReal
checkAllThetaRelErrorReal
Golden Theorems:

#check verify_theta_le_mul
Range checkers have corresponding range Golden Theorems:

#check verify_all_theta_le_mul
For real x ∈ [N, N+1), use the strengthened interval certificate:

#check verify_theta_rel_error_real

Example

import LeanCert.Engine.Chebyshev.Psi

open Chebyshev (psi)
open LeanCert.Engine.Chebyshev.Psi

example :
     N : Nat, 0 < N  N  20 
      psi (N : )  (3 : ) * N := by
  exact verify_all_psi_le_mul 20 20 3 (by native_decide)

Notes

The older theorem names such as psi_le_of_checkPsiLeMulWith and abs_theta_sub_le_mul_of_checkThetaRelError remain available. The verify_* names are thin public aliases matching the rest of LeanCert's Golden Theorem style.