Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.
Updated
Claim. Kenneth A. Mendoza's Zenodo deposits Computational verification of
the Erdős–Herzog–Piranian conjecture, six versions from 2026-03-23 to
2026-05-08, assert that for every degree from up to the version's top
degree (, then , and ) every monic polynomial of degree has
a lemniscate no longer than that of , the instances of
Problem 114 in those degrees. The method
is a branch-and-bound search over a bounded box of coefficients, reduced by
symmetry to real parameters, in which interval arithmetic (the Rust
library inari, IEEE 1788) carries the sums, a Lipschitz margin bounds each
box, and a marching-squares computation in floating point estimates each
lemniscate's length; the deposits also give the closed form
and a numerical Hessian at .
The author announced the search on the site's discussion thread on 2026-03-27
(degrees to ) and on 2026-05-08 (degrees to , with release
v3.1.0 of the code, which replaced a degree-13 row whose run had evaluated no
boxes), presenting it as the finite complement of Tao's theorem for large
degrees and claiming nothing for .
Submission note. Posted to the site's forum by Kenneth A. Mendoza on 27 March 2026:
We have computationally verified the EHP conjecture for all degrees $3 \leq n \leq 12$ using dual independent implementations (Python/mpmath and Rust/inari) with IEEE 1788 certified interval arithmetic and branch-and-bound optimization. Both implementations produce identical certified enclosures across x86_64 and arm64 architectures. The dominance margins increase monotonically from () to (); all non-extremizer boxes are eliminated at level for . We also derive a new closed-form expression for valid for all .
Combined with Tao's result [Ta25] for sufficiently large , the conjecture is now verified for all and all . The remaining gap is .
Preprint and certified result JSON files with SHA-256 checksums: doi.org/10.5281/zenodo.19229245
Code: github.com/MendozaLab/erdos-experiments
Withdrawal. Issue #4 of the code repository, opened on 2026-08-25 by Bertrand Chatelet, objects that the lemniscate lengths come from floating-point marching squares with an added margin of five percent, that the Lipschitz constant is estimated by finite differences at several scales, and that the Hessian is a central-difference approximation, so that none of the three is a bound and the chain of certification is broken; Chatelet pointed to the issue on the site's thread on 2026-09-05. The author's reply of 2026-10-01 accepts the three objections and reports an audit of the engine that found more: for a closed-interval test marked half of the coefficient box, the half containing , as extremizer boxes that were never evaluated, and the outer region of coefficient space was covered by pseudo-random samples, not by a bound. The author states that the deposits are a computational census consistent with the conjecture, and not a proof, a certificate or an independently checked result for any degree from to , and announces a corrected Zenodo version and a reply on the site's thread. The claim is recorded as withdrawn by its author.
Covers. Degrees to , as claimed; nothing is settled. Degree is settled by Wang 1998 and Eremenko–Hayman 1999, and all sufficiently large degrees are claimed, pending, by Tao 2025.
Depends on. No page of this wiki.