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Unbounded Positivity of the Separable Record Newton Kernels

Abstract

Every record Newton kernel has nonnegative coefficients after actual scalar substitution.

Theorem 1.1 (Every natural kernel index and every natural length index).

Proof. Machine-checked in Lean as D5/S1/Words/Patterns/Separable/RecordNewtonPositivity.actual_q_record_newton_nonnegative (✓ std3). ∎

Source. Repository-derived.

Commentary.

The theorem quantifies over all natural r and n. The scalar q(t) is the actual positive 2413/3142-avoider counting series, identified by the frozen cardinality supplier with t*largeSchroderSeries. It satisfies q=t+tq+q^2 and t(1+q)=q(1-q). Its constant is zero and every coefficient is nonnegative.

In an independent formal variable u, put a=u(3+2u), b=u(1+u)^3 and c=u(4+3u)=4b-a^2. The source constructs M(z)=(1-az)^(-1) C(bz^2/(1-az)^2) from Mathlib’s Catalan series C. Its coefficient T_r satisfies T_0=1, T_1=a and (r+4)T_(r+2)=(2r+5)aT_(r+1)+(r+1)cT_r at every index.

Define G_r=(1+u)^2(T_r+T_(r+1)) -u(1-u)(1+u)(T_r+2T_(r+1)+T_(r+2)). The conclusion is coefficientwise nonnegativity of G_r(q(t)), without a cutoff in either index. For a polynomial f, the proof constructs V with (1-2u-u^2)V=(1+u)^2 f’. Exact initial coefficient identities and the universal recurrence v_(m+2)=2v_(m+1)+v_m prove V is nonnegative. The chain rule and formal integration prove f(q(t)) is nonnegative when f(0)>=0.

This certificate rule treats G_0 through G_11. Let E1=(1+u)^2(1-u-2u^2+3u^3) and E2=(1+u)^2(1-2u-2u^2+4u^3). Two consecutive certificates for E1T_1 and E1T_2 propagate to every r>=1. Two for E2T_13 and E2T_14 propagate to every r>=13. The universal Motzkin recurrence gives (r+4)G_r=(r+4)(E1T_r+E2T_(r+1)) +3u(1-u)(1+u)(cT_r+aT_(r+1)). After substitution the last summand is nonnegative by t(1+q)=q(1-q). This proves every r>=12 and completes the all-index sign law.

The new content is the live all-index differential recurrence and positivity propagation, with all necessary steps local to one public theorem. Local definitions and compiler-generated equations receive no separate novelty credit. This is a partial unbounded result. The normalized actual J coefficient formula and its Newton transform are still needed before this sign law implies the actual declining comparisons at every k>=4. Those comparisons, the global maximum at three and complete CKZ Conjecture 2 remain open. No KPI increment is claimed. Reg enrollment is user-paused; no completed escape audit is claimed.

References