PF000C

pythagorean_primitive_leg_swap

Alpha v34 independently verified · alpha_closed; checked-use authorized; not Stable

Primitive Pythagorean triples remain primitive after swapping their legs, with coprimality proved by explicit common-divisor witnesses.

Current library: Alpha v34, 4,223 checked-use theorems; Stable remains 432. Historical first admissions, original proof editions, and non-admitted aliases are preserved. Exact original first-admission records.

Exact expanded first-order arithmetic statement

forall x y z. ((((x) * (x) + (y) * (y) = (z) * (z)) /\ (forall pff_divisor_source. (exists pff_left_source. (x) = pff_divisor_source * pff_left_source) -> (exists pff_right_source. (y) = pff_divisor_source * pff_right_source) -> pff_divisor_source = 1))) -> ((((y) * (y) + (x) * (x) = (z) * (z)) /\ (forall pff_divisor_swapped. (exists pff_left_swapped. (y) = pff_divisor_swapped * pff_left_swapped) -> (exists pff_right_swapped. (x) = pff_divisor_swapped * pff_right_swapped) -> pff_divisor_swapped = 1)))

Constructive proof overview

Generated structural guide

Primitive Pythagorean triples remain primitive after swapping their legs, with coprimality proved by explicit common-divisor witnesses.

The unchanged tactic script uses 2 declared prerequisites and contains 10 exact native proof lines.

dependency-curried kernel-checked theorem body; Alpha enrollment and checked-use authority follow separately sealed release evidence; Stable membership remains unchanged

Proof neighborhood

Direct dependencies

Direct dependents

Formal native tactic body

Dependencies are introduced as named hypotheses before line 1. Local theorem links identify exact declared prerequisites. This exact body belongs to a complete independently kernel-checked constructive proof bundle and has Alpha checked-use authority; it does not imply Stable membership.

Read the argument

Proof checkpoints

10 script commands · 3 reading checkpoints · 0 local claims

This is a reading aid, not a new proof or a proof-tree certificate. Checkpoint groups are consecutive commands, not inferred branch boundaries. Every step links to the preserved script.

Named ingredients (2)
01Fix variables and assumptionsL1–4

Work with arbitrary variables or the premises of the current implication.

  1. L1
    intro x
  2. L2
    intro y
  3. L3
    intro z
  4. L4
    intro hprimitive
02Separate the logical casesL5–6

Follow the explicit conjunction, disjunction, witness, or contradiction step recorded below.

  1. L5
    cases hprimitive
  2. L6
    split
03Use earlier factsL7–10

Instantiate or apply named facts and discharge the corresponding proof obligations.

  1. L7
    apply pythagorean_leg_swap
  2. L8
    exact hprimitive_left
  3. L9
    apply pythagorean_coprime_swap
  4. L10
    exact hprimitive_right

Library-wide reading audit

Original exact command ledger · 10 lines
  1. 0001intro x
  2. 0002intro y
  3. 0003intro z
  4. 0004intro hprimitive
  5. 0005cases hprimitive
  6. 0006split
  7. 0007apply pythagorean_leg_swap
  8. 0008exact hprimitive_left
  9. 0009apply pythagorean_coprime_swap
  10. 0010exact hprimitive_right