BT008J

all_bits_prefix_succ

Stable checked-use theorem · independently kernel verified

Dropping the final entry preserves the all-bits invariant.

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 b c l sl. sl = S l -> (forall ff_i_successor. (exists ff_lt_successor_bound. ff_lt_successor_bound + S ff_i_successor = sl) -> exists ff_bit_successor. ((((exists ff_h_successor_decoded. ff_h_successor_decoded + S (ff_bit_successor) = S ((S (ff_i_successor)) * c)) /\ exists ff_q_successor_decoded. b = ff_q_successor_decoded * S ((S (ff_i_successor)) * c) + (ff_bit_successor))) /\ (ff_bit_successor = 0 \/ ff_bit_successor = 1))) -> (forall ff_i_prefix. (exists ff_lt_prefix_bound. ff_lt_prefix_bound + S ff_i_prefix = l) -> exists ff_bit_prefix. ((((exists ff_h_prefix_decoded. ff_h_prefix_decoded + S (ff_bit_prefix) = S ((S (ff_i_prefix)) * c)) /\ exists ff_q_prefix_decoded. b = ff_q_prefix_decoded * S ((S (ff_i_prefix)) * c) + (ff_bit_prefix))) /\ (ff_bit_prefix = 0 \/ ff_bit_prefix = 1)))

Structural proof guide

Dropping the final entry preserves the all-bits invariant.

Direct prerequisites: le_succ. The authored body proceeds by equality transport (1).

Proof neighborhood

Direct dependencies

Direct dependents

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

15 script commands · 4 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 (1)
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 sl
  5. L5
    intro hsl
  6. L6
    intro hbits
02Calculate and transport equalitiesL7–7

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

  1. L7
    rewrite hsl at hbits
03Fix variables and assumptionsL8–9

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

  1. L8
    intro i
  2. L9
    intro hi
04Use earlier factsL10–15

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

  1. L10
    specialize hbits i
  2. L11
    apply hbits
  3. L12
    specialize le_succ (S i)
  4. L13
    specialize le_succ l
  5. L14
    apply le_succ
  6. L15
    exact hi

Library-wide reading audit

Original exact command ledger · 15 lines
  1. 0001intro b
  2. 0002intro c
  3. 0003intro l
  4. 0004intro sl
  5. 0005intro hsl
  6. 0006intro hbits
  7. 0007rewrite hsl at hbits
  8. 0008intro i
  9. 0009intro hi
  10. 0010specialize hbits i
  11. 0011apply hbits
  12. 0012specialize le_succ (S i)
  13. 0013specialize le_succ l
  14. 0014apply le_succ
  15. 0015exact hi