PA009F

scaled_inverse_fixed_point_iff

Alpha v34 checked-use theorem · independently closed; not Stable

On the bounded unit domain, fixed points are exactly square roots of a.

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 PA statement

forall p a x. ((((((~(x = 0) /\ (exists esi_strict_gap_fixed_relation_left_bound. esi_strict_gap_fixed_relation_left_bound + S x = p))) /\ (((~(x = 0) /\ (exists esi_strict_gap_fixed_relation_right_bound. esi_strict_gap_fixed_relation_right_bound + S x = p))) /\ (exists esi_mod_left_fixed_relation_mod esi_mod_right_fixed_relation_mod. (x * x) + p * esi_mod_left_fixed_relation_mod = (a) + p * esi_mod_right_fixed_relation_mod)))) -> ((((~(x = 0) /\ (exists esi_strict_gap_fixed_square_unit_bound. esi_strict_gap_fixed_square_unit_bound + S x = p))) /\ (exists esi_mod_left_fixed_square_square esi_mod_right_fixed_square_square. (x * x) + p * esi_mod_left_fixed_square_square = (a) + p * esi_mod_right_fixed_square_square)))) /\ (((((~(x = 0) /\ (exists esi_strict_gap_fixed_square_unit_bound. esi_strict_gap_fixed_square_unit_bound + S x = p))) /\ (exists esi_mod_left_fixed_square_square esi_mod_right_fixed_square_square. (x * x) + p * esi_mod_left_fixed_square_square = (a) + p * esi_mod_right_fixed_square_square))) -> ((((~(x = 0) /\ (exists esi_strict_gap_fixed_relation_left_bound. esi_strict_gap_fixed_relation_left_bound + S x = p))) /\ (((~(x = 0) /\ (exists esi_strict_gap_fixed_relation_right_bound. esi_strict_gap_fixed_relation_right_bound + S x = p))) /\ (exists esi_mod_left_fixed_relation_mod esi_mod_right_fixed_relation_mod. (x * x) + p * esi_mod_left_fixed_relation_mod = (a) + p * esi_mod_right_fixed_relation_mod))))))

Structural proof guide

Generated structural guide

On the bounded unit domain, fixed points are exactly square roots of a.

This root lemma is proved directly from the PA rules and the hypotheses introduced by its statement.

The proof proceeds by case analysis (3).

Referenced ingredients

none

Proof neighborhood

Direct dependencies

none

Direct dependents

Formal native tactic body

Dependencies are introduced as named hypotheses before line 1. Linked names are exact direct references. This Alpha-v25 checked-use theorem is independently kernel-checked when replayed; it is not a Stable theorem.

Read the argument

Proof checkpoints

17 script commands · 10 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.

01Fix variables and assumptionsL1–3

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

  1. L1
    intro p
  2. L2
    intro a
  3. L3
    intro x
02Separate the logical casesL4–4

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

  1. L4
    split
03Fix variables and assumptionsL5–5

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

  1. L5
    intro hrel
04Separate the logical casesL6–8

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

  1. L6
    cases hrel
  2. L7
    cases hrel_right
  3. L8
    split
05Use earlier factsL9–10

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

  1. L9
    exact hrel_left
  2. L10
    exact hrel_right_right
06Fix variables and assumptionsL11–11

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

  1. L11
    intro hfixed
07Separate the logical casesL12–13

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

  1. L12
    cases hfixed
  2. L13
    split
08Use earlier factsL14–14

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

  1. L14
    exact hfixed_left
09Separate the logical casesL15–15

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

  1. L15
    split
10Use earlier factsL16–17

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

  1. L16
    exact hfixed_left
  2. L17
    exact hfixed_right

Library-wide reading audit

Original exact command ledger · 17 lines
  1. 0001intro p
  2. 0002intro a
  3. 0003intro x
  4. 0004split
  5. 0005intro hrel
  6. 0006cases hrel
  7. 0007cases hrel_right
  8. 0008split
  9. 0009exact hrel_left
  10. 0010exact hrel_right_right
  11. 0011intro hfixed
  12. 0012cases hfixed
  13. 0013split
  14. 0014exact hfixed_left
  15. 0015split
  16. 0016exact hfixed_left
  17. 0017exact hfixed_right