BT0019

lt_to_le

Stable ยท empty-context checked

A witnessed strict inequality entails the corresponding weak inequality.

Exact expanded PA statement

forall a b. (exists k. k + S a = b) -> exists r. r + a = b

Structural proof guide

A witnessed strict inequality entails the corresponding weak inequality.

Direct prerequisites: add_succ_left. The authored body proceeds by case analysis (1).

Proof neighborhood

Direct dependencies

Direct dependents

Formal native tactic body

Dependencies are hypotheses of this body receipt. The focused endpoint audits separately check the complete empty-context certificates.

  1. 0001intro a
  2. 0002intro b
  3. 0003intro h
  4. 0004cases h
  5. 0005exists S x
  6. 0006trans x + S a
  7. 0007trans S (x + a)
  8. 0008apply add_succ_left
  9. 0009symm
  10. 0010apply PA4
  11. 0011exact h_witness