Mathlib v4.30 source proposition Nat.fib_add_two

Identifier: F:ml430-nat-fib-add-two-b86e0c82
Proof route: kernel-lean
External status: proved
Axiom footprint: Empty

Recorded description

The proposition declared as `Nat.fib_add_two` in the pinned Mathlib v4.30 source.

Formal statement

∀ {n : ℕ}, Nat.fib (n + 2) = Nat.fib n + Nat.fib (n + 1)

Dependencies

The graph shows direct ledger edges. Follow a node to open its artifact page.

1 direct dependencies 11 direct dependents Graph shows the first 8 on each side.

Evidence

autogenesis-operation-d55dac246e5d4ffc

Kind: kernel-term
Status: checked

Supports: The proposition declared as `Nat.fib_add_two` in the pinned Mathlib v4.30 source.

Checker command

python3 scripts/check-autogenesis-fact-operation.py --fact artifacts/facts/F-ml430-nat-fib-add-two-b86e0c82.json

Evidence notes

Derived from a clean-commit typed execution receipt. The registered fact-operation checker replays the immutable source-bound semantic theorem receipt and requires its exact two-fresh-kernel proof, zero assumptions, and zero direct theorem dependencies; no caller-authored route, footprint, checker, or shell command is accepted.

Provenance

{
  "date": "2026-08-18",
  "established_by": "axeyum-autogenesis execution f0fb2c6f374ba6255e9acdd63582e10db41b8ba094fb97149df667acdfc0030b",
  "prior_art": [
    {
      "attribution": "the proposition was read from the pinned statement-only inventory; the proof term and tactic trace were not consulted",
      "what": "the theorem declaration `Nat.fib_add_two`",
      "where": "mathlib4 commit c5ea00351c28e24afc9f0f84379aa41082b1188f (v4.30.0)",
      "who": "the Mathlib contributors",
      "year": 2026
    }
  ],
  "source": "statement-only extraction of `Nat.fib_add_two` from Mathlib v4.30.0; no proof value was exposed"
}