BT008L · Bertrand theorem

bit_count_exists

Stable checked-use theorem · independently kernel verified

Every all-bits prefix has a relational count of its ones.

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.

Statement with defined notation

∀ b. ∀ c. ∀ l. AllBits(b,c,l) → ∃ x. BitCount(b,c,l,x)

Every purple notation token opens its conservative definition. Expanding the displayed statement recovers the exact first-order Peano-arithmetic formula checked by the unchanged kernel.

Definitions used by this theorem

In the theorem statement

2 occurrences

In local proof propositions

none

0 occurrences

Exact expanded native-PA statement
forall b c l. (forall ff_i_a. (exists ff_lt_a_bound. ff_lt_a_bound + S ff_i_a = l) -> exists ff_bit_a. ((((exists ff_h_a_decoded. ff_h_a_decoded + S (ff_bit_a) = S ((S (ff_i_a)) * c)) /\ exists ff_q_a_decoded. b = ff_q_a_decoded * S ((S (ff_i_a)) * c) + (ff_bit_a))) /\ (ff_bit_a = 0 \/ ff_bit_a = 1))) -> exists n. (((exists ff_u_b_sum ff_v_b_sum. ((((exists ff_h_b_sum_start. ff_h_b_sum_start + S (0) = S ((S (0)) * ff_v_b_sum)) /\ exists ff_q_b_sum_start. ff_u_b_sum = ff_q_b_sum_start * S ((S (0)) * ff_v_b_sum) + (0))) /\ ((((exists ff_h_b_sum_terminal. ff_h_b_sum_terminal + S (n) = S ((S (l)) * ff_v_b_sum)) /\ exists ff_q_b_sum_terminal. ff_u_b_sum = ff_q_b_sum_terminal * S ((S (l)) * ff_v_b_sum) + (n))) /\ forall ff_i_b_sum. (exists ff_lt_b_sum_bound. ff_lt_b_sum_bound + S ff_i_b_sum = l) -> exists ff_a_b_sum ff_r_b_sum ff_s_b_sum. ((((exists ff_h_b_sum_summand. ff_h_b_sum_summand + S (ff_a_b_sum) = S ((S (ff_i_b_sum)) * c)) /\ exists ff_q_b_sum_summand. b = ff_q_b_sum_summand * S ((S (ff_i_b_sum)) * c) + (ff_a_b_sum))) /\ ((((exists ff_h_b_sum_partial. ff_h_b_sum_partial + S (ff_r_b_sum) = S ((S (ff_i_b_sum)) * ff_v_b_sum)) /\ exists ff_q_b_sum_partial. ff_u_b_sum = ff_q_b_sum_partial * S ((S (ff_i_b_sum)) * ff_v_b_sum) + (ff_r_b_sum))) /\ ((((exists ff_h_b_sum_successor. ff_h_b_sum_successor + S (ff_s_b_sum) = S ((S (S ff_i_b_sum)) * ff_v_b_sum)) /\ exists ff_q_b_sum_successor. ff_u_b_sum = ff_q_b_sum_successor * S ((S (S ff_i_b_sum)) * ff_v_b_sum) + (ff_s_b_sum))) /\ ff_s_b_sum = ff_r_b_sum + ff_a_b_sum)))))) /\ (forall ff_i_b_bits. (exists ff_lt_b_bits_bound. ff_lt_b_bits_bound + S ff_i_b_bits = l) -> exists ff_bit_b_bits. ((((exists ff_h_b_bits_decoded. ff_h_b_bits_decoded + S (ff_bit_b_bits) = S ((S (ff_i_b_bits)) * c)) /\ exists ff_q_b_bits_decoded. b = ff_q_b_bits_decoded * S ((S (ff_i_b_bits)) * c) + (ff_bit_b_bits))) /\ (ff_bit_b_bits = 0 \/ ff_bit_b_bits = 1)))))

Proof neighborhood

Direct theorem prerequisites

Direct theorem dependents

Definition-aware tactic body

Only local propositions introduced by have or suffices are compacted. Every changed line has an exact-AST conservative-expansion receipt; the kernel still receives the immutable original tactic script.

Read the argument

Proof checkpoints

12 script commands · 6 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.

Definition notation is shown below. Open the paired exact edition for the original native formulas. Source pairing is not a new equivalence certificate.

Named ingredients (1)
01Fix variables and assumptionsL1–4

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 hbits
02Use earlier factsL5–7

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

  1. L5
    specialize beta_sum_exists b
  2. L6
    specialize beta_sum_exists c
  3. L7
    specialize beta_sum_exists l
03Separate the logical casesL8–8

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

  1. L8
    cases beta_sum_exists
04Construct an explicit witnessL9–9

Supply the displayed value, then prove that it has the required property.

  1. L9
    exists x
05Separate the logical casesL10–10

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

  1. L10
    split
06Use earlier factsL11–12

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

  1. L11
    exact beta_sum_exists_witness
  2. L12
    exact hbits

Library-wide reading audit

Original defined command ledger · 12 lines
  1. 0001intro b
  2. 0002intro c
  3. 0003intro l
  4. 0004intro hbits
  5. 0005specialize beta_sum_exists b
  6. 0006specialize beta_sum_exists c
  7. 0007specialize beta_sum_exists l
  8. 0008cases beta_sum_exists
  9. 0009exists x
  10. 0010split
  11. 0011exact beta_sum_exists_witness
  12. 0012exact hbits