BT001B

lt_irrefl_expanded

Stable checked-use theorem · independently kernel verified

No natural is strictly below itself, with strict order fully expanded.

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 n. ~(exists k. k + S n = n)

Structural proof guide

No natural is strictly below itself, with strict order fully expanded.

Direct prerequisites: add_succ_left, no_succ_add_fixed. The authored body proceeds by case analysis (1).

Proof neighborhood

Direct dependencies

BT0001 add_succ_left BT000G no_succ_add_fixed

Direct dependents

BT0059 beta_exclusive_accumulated_product_step BT00R2 ceil_div_six_functional BT00RF ceil_div_six_le_of_upper BT00TG choose_self BT00VD beta_pairwise_coprime_product_divides_common_multiple BT00YC double_quotient_carry_prefix_entries_zero BT010B floor_sqrt_two_le_of_two_lt

Formal native tactic body

Dependencies are hypotheses of the historical Alpha-v12 body receipt. The complete historical Alpha-v18 proof bundle independently checks every dependency; current Alpha v25 preserves that checked theorem use without changing Stable membership.

Read the argument

Proof checkpoints

12 script commands · 7 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)
add succ leftno succ add fixed
01Fix variables and assumptionsL1–2

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

  1. L1
    intro n
  2. L2
    intro h
02Separate the logical casesL3–3

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

  1. L3
    cases h
03Use earlier factsL4–6

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

  1. L4
    specialize no_succ_add_fixed x
  2. L5
    specialize no_succ_add_fixed n
  3. L6
    apply no_succ_add_fixed
04Calculate and transport equalitiesL7–8

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

  1. L7
    trans x + S n
  2. L8
    trans S (x + n)
05Use earlier factsL9–9

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

  1. L9
    apply add_succ_left
06Calculate and transport equalitiesL10–10

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

  1. L10
    symm
07Use earlier factsL11–12

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

  1. L11
    apply PA4
  2. L12
    exact h_witness

Library-wide reading audit

Original exact command ledger · 12 lines
  1. 0001intro n
  2. 0002intro h
  3. 0003cases h
  4. 0004specialize no_succ_add_fixed x
  5. 0005specialize no_succ_add_fixed n
  6. 0006apply no_succ_add_fixed
  7. 0007trans x + S n
  8. 0008trans S (x + n)
  9. 0009apply add_succ_left
  10. 0010symm
  11. 0011apply PA4
  12. 0012exact h_witness