Diagonal stabilization theorem: for each offset j>=0, [t^{n+j}] phi_t^n(-1) = A_j is CONSTANT for all n>=max(j,1), with A_0=-1 and A_j=[t^{2j}]phi_t^j(-1) for j>=1. Equivalently phi_t^n(-1) = t^n*Phi(t) mod t^{2n+1} for a single fixed profile Phi(t)=sum_{j>=0} A_j t^j independent of n. Proof: in e^{t f_n}-1=sum_m (t f_n)^m/m!, the term m>=2 has valuation m(n+1)>n+1+j whenever n>=j, so only m=1 contributes to degree n+1+j. The threshold n>=max(j,1) is tight (e.g. c^(2)_5=-11/24 != 1/24 = A_3).
Evidence
Provenance
Reviews
Diagonal-stabilization valuation argument correct; threshold tightness independently confirmed (c(2)_5=-11/24, c(1)_3=-1/6).
Referee-commissioned independent blind review (Fable-5). GENERATIVE-LAYER DISJOINT reproduction: an own from-scratch pure-Fraction reimplementation (not the author's code) matches all values incl. the extremal 2663/4480 at (6,13), the exact N=1000 certificate, the N=700 arb scan, and the Lean cert recompiled on the pinned toolchain. The native_decide finite check does NOT masquerade as a general proof (outcome=partial, finite-window scope + TCB disclosed). Fable lean: GREEN. Referee note: this corroborates the Rippon synthesis; final green CALL pending referee sign-off. Nits: arb receipt in-repo covers N=600 vs claimed 700 (disclosed, reproduced); code_refs use the post-amendment prefix.