TF0002

beta_two_square_prefix_last_represented

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

The final decoded factor of a represented successor prefix has its own explicit two-square 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 b c l a. (forall ftsf_index_drop_next ftsf_factor_drop_next. (exists ftsf_gap_drop_next_bound. ftsf_gap_drop_next_bound + S ftsf_index_drop_next = (S l)) -> (((exists ff_h_ftsf_drop_next_entry. ff_h_ftsf_drop_next_entry + S (ftsf_factor_drop_next) = S ((S (ftsf_index_drop_next)) * c)) /\ exists ff_q_ftsf_drop_next_entry. b = ff_q_ftsf_drop_next_entry * S ((S (ftsf_index_drop_next)) * c) + (ftsf_factor_drop_next))) -> (exists ftsf_first_drop_next_representation ftsf_second_drop_next_representation. (ftsf_factor_drop_next) = ftsf_first_drop_next_representation * ftsf_first_drop_next_representation + ftsf_second_drop_next_representation * ftsf_second_drop_next_representation)) -> (((exists ff_h_ftsf_last_entry. ff_h_ftsf_last_entry + S (a) = S ((S (l)) * c)) /\ exists ff_q_ftsf_last_entry. b = ff_q_ftsf_last_entry * S ((S (l)) * c) + (a))) -> (exists ftsf_first_last_result ftsf_second_last_result. (a) = ftsf_first_last_result * ftsf_first_last_result + ftsf_second_last_result * ftsf_second_last_result)

Constructive proof overview

Generated structural guide

The final decoded factor of a represented successor prefix has its own explicit two-square witnesses.

The unchanged tactic script uses 1 declared prerequisite and contains 12 exact native proof lines.

Alpha v34 checked-use · first admitted v23 · independently kernel and Lean verified; not Stable

Proof neighborhood

Direct dependencies

le_refl Stable theorem; checked-use authorized

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

12 script commands · 2 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 assumptionsL1–6

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

  1. L1
    intro b
  2. L2
    intro c
  3. L3
    intro l
  4. L4
    intro a
  5. L5
    intro hprefix
  6. L6
    intro hlast
02Use earlier factsL7–12

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

  1. L7
    specialize hprefix l
  2. L8
    specialize hprefix a
  3. L9
    apply hprefix
  4. L10
    specialize le_refl (S l)
  5. L11
    exact le_refl
  6. L12
    exact hlast

Library-wide reading audit

Original exact command ledger · 12 lines
  1. 0001intro b
  2. 0002intro c
  3. 0003intro l
  4. 0004intro a
  5. 0005intro hprefix
  6. 0006intro hlast
  7. 0007specialize hprefix l
  8. 0008specialize hprefix a
  9. 0009apply hprefix
  10. 0010specialize le_refl (S l)
  11. 0011exact le_refl
  12. 0012exact hlast