LU000V

lucas_predecessor_digit_below_base

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

The predecessor of a nonzero digit strictly below the base remains strictly below the base.

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 p k. (exists lcv_gap_predecessor_source. lcv_gap_predecessor_source + S (S k) = (p)) -> (exists lcv_gap_predecessor_result. lcv_gap_predecessor_result + S (k) = (p))

Constructive proof overview

Generated structural guide

The predecessor of a nonzero digit strictly below the base remains strictly below the base.

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

Historical empty-context replay experiment only; that experiment persisted no certificate and granted no release authority. Current checked use follows separately sealed, independently verified proof bundles; there is no Stable promotion.

Proof neighborhood

Direct dependencies

le_succ_self Stable theorem; checked-use authorized le_trans 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

10 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 assumptionsL1–3

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

  1. L1
    intro p
  2. L2
    intro k
  3. L3
    intro hbound
02Use earlier factsL4–10

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

  1. L4
    specialize le_trans (S k)
  2. L5
    specialize le_trans (S (S k))
  3. L6
    specialize le_trans p
  4. L7
    apply le_trans
  5. L8
    specialize le_succ_self (S k)
  6. L9
    exact le_succ_self
  7. L10
    exact hbound

Library-wide reading audit

Original exact command ledger · 10 lines
  1. 0001intro p
  2. 0002intro k
  3. 0003intro hbound
  4. 0004specialize le_trans (S k)
  5. 0005specialize le_trans (S (S k))
  6. 0006specialize le_trans p
  7. 0007apply le_trans
  8. 0008specialize le_succ_self (S k)
  9. 0009exact le_succ_self
  10. 0010exact hbound