BT0056 · Bertrand theorem

scaled_bounded_common_multiple

Stable checked-use theorem · independently kernel verified

A right multiple of a bounded common multiple remains such a common multiple.

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

∀ N. ∀ C. ∀ B. (∀ x. (∃ y. S x + S y = S N) → Dvd(S x,C)) → ∀ x. (∃ y. S x + S y = S N) → Dvd(S x,C · B)

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

1 occurrences

Exact expanded native-PA statement
forall N C B. (forall t. (exists h. S t + S h = S N) -> exists q. C = S t * q) -> forall t. (exists h. S t + S h = S N) -> exists q. C * B = S t * q

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

15 script commands · 2 reading checkpoints · 1 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 assumptionsL1–6

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

  1. L1
    intro N
  2. L2
    intro C
  3. L3
    intro B
  4. L4
    intro hcm
  5. L5
    intro t
  6. L6
    intro ht
02Establish htCL7–15

Establish this local claim before using it. It is not an additional assumption. The following proof commands apply hcm.

  1. L7
  2. L8
    specialize hcm t
  3. L9
    apply hcm
  4. L10
    exact ht
  5. L11
    specialize multiple_mul_right (S t)
  6. L12
    specialize multiple_mul_right C
  7. L13
    specialize multiple_mul_right B
  8. L14
    apply multiple_mul_right
  9. L15
    exact htC

Library-wide reading audit

Original defined command ledger · 15 lines
  1. 0001intro N
  2. 0002intro C
  3. 0003intro B
  4. 0004intro hcm
  5. 0005intro t
  6. 0006intro ht
  7. 0007have htC : Dvd(S t,C)
    Exact native replay linehave htC : exists q. C = S t * q
  8. 0008specialize hcm t
  9. 0009apply hcm
  10. 0010exact ht
  11. 0011specialize multiple_mul_right (S t)
  12. 0012specialize multiple_mul_right C
  13. 0013specialize multiple_mul_right B
  14. 0014apply multiple_mul_right
  15. 0015exact htC