Canonical Fibonacci Carry Barrier
Abstract
Strict conjugate estimates bound how far a high Fibonacci addition can change canonical support.
Theorem 1.1 (Lower boundary after high addition).
Lean statement: D5/S1/Digit/ZeckendorfCarryBarrier.lower_support_carry_barrier
Proof. Machine-checked in Lean as D5/S1/Digit/ZeckendorfCarryBarrier.lower_support_carry_barrier (✓ std3). ∎
Source. Repository-derived.
Commentary.
The complete statement is theorem lower_support_carry_barrier (P : List ℕ) (m j : ℕ) (hP : P.IsZeckendorfRep) (hm : 4 ≤ m) (hmin : ∀ k ∈ P, m ≤ k) (hj : m - 1 ≤ j) : ∀ k ∈ wdigits ((P.map Nat.fib).sum + Nat.fib j), m - 2 ≤ k.
If P is canonical, m is at least four, every index of P is at least m, and j is at least m minus one, then every index in the canonical support of the sum of P and F_j is at least m minus two. Empty supports and the boundary index are included. Strict finite tails and the open conjugate interval of length one identify the normalized error; least-digit dominance gives the support bound.
References
- Truth anchor:
D5/S1/Digit/ZeckendorfCarryBarrier.lower_support_carry_barrier - Dependency: D5/S1/Words/ZeckendorfBeattyBridge