SL0001

prime_predecessor_nonzero

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

The predecessor of a prime cannot be zero.

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 n. p = S n -> ((~(p = 1) /\ forall frm_prime_left_qsm_prime frm_prime_right_qsm_prime. p = frm_prime_left_qsm_prime * frm_prime_right_qsm_prime -> frm_prime_left_qsm_prime = 1 \/ frm_prime_right_qsm_prime = 1)) -> ~(n = 0)

Constructive proof overview

Generated structural guide

The predecessor of a prime cannot be zero.

The unchanged tactic script uses 0 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

none

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 · 5 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 assumptionsL1–4

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

  1. L1
    intro p
  2. L2
    intro n
  3. L3
    intro hpredecessor
  4. L4
    intro hprime
02Separate the logical casesL5–5

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

  1. L5
    cases hprime
03Fix variables and assumptionsL6–6

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

  1. L6
    intro hzero
04Use earlier factsL7–7

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

  1. L7
    apply hprime_left
05Calculate and transport equalitiesL8–10

Carry out the recorded arithmetic or equality steps; inspect the exact commands for their direction and premises.

  1. L8
    rewrite hpredecessor
  2. L9
    rewrite hzero
  3. L10
    refl

Library-wide reading audit

Original exact command ledger · 10 lines
  1. 0001intro p
  2. 0002intro n
  3. 0003intro hpredecessor
  4. 0004intro hprime
  5. 0005cases hprime
  6. 0006intro hzero
  7. 0007apply hprime_left
  8. 0008rewrite hpredecessor
  9. 0009rewrite hzero
  10. 0010refl