BT0055

le_scaled_nonzero

Stable ยท empty-context checked

Scaling by a nonzero natural does not decrease a natural.

Exact expanded PA statement

forall C B. ~(C = 0) -> exists h. h + B = C * B

Structural proof guide

Scaling by a nonzero natural does not decrease a natural.

Direct prerequisites: one_le_of_ne_zero, mul_le_mul_right, one_mul. The authored body proceeds by intermediate claims (2), equality transport (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 C
  2. 0002intro B
  3. 0003intro hC
  4. 0004have h1C : exists h. h + 1 = C
  5. 0005specialize one_le_of_ne_zero C
  6. 0006apply one_le_of_ne_zero
  7. 0007exact hC
  8. 0008have hscaled : exists h. h + 1 * B = C * B
  9. 0009specialize mul_le_mul_right 1
  10. 0010specialize mul_le_mul_right C
  11. 0011specialize mul_le_mul_right B
  12. 0012apply mul_le_mul_right
  13. 0013exact h1C
  14. 0014specialize one_mul B
  15. 0015rewrite one_mul at hscaled
  16. 0016exact hscaled