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Claim. Let p(z)=∏i=1n(z−zi)p(z)=\prod_{i=1}^n(z-z_i) with every ∣zi∣≤1\lvert z_i\rvert\le1. Then {z:∣p(z)∣≤1}\{z:\lvert p(z)\rvert\le1\} contains a disk of radius (2e)−1n−2(2e)^{-1}n^{-2} about one of the zeros, so

∣{z:∣p(z)∣<1}∣≥π (2e)−2 n−4,\lvert\{z:\lvert p(z)\rvert<1\}\rvert\ge\pi\,(2e)^{-2}\,n^{-4},

the open set included, since every point of that disk has modulus below 11. This is Theorem 4 of Pommerenke, On metric properties of complex polynomials, Michigan Math. J. 8 (1961), no. 2, 97–115 (Theorem 4, printed p. 101), recorded on the result page [[../library/analysis/pommerenke_1961_metric_properties_complex_polynomials/theorem_4|Theorem 4]] of the card [[../library/analysis/pommerenke_1961_metric_properties_complex_polynomials/_index|Pommerenke 1961]]. It answers the question of Problem 116 yes: the area is at least n−O(1)n^{-O(1)}, with exponent 44. The proof combines the diameter bound of the paper's Theorem 3 (the component through 00 has diameter above 11, hence capacity above 1/41/4) with the derivative bound ∣p′∣<2en2\lvert p'\rvert<2en^2 on that component, and integrates from a zero to the nearest point of modulus 11. The parenthetical stronger form, an area of at least (log⁡n)−O(1)(\log n)^{-O(1)}, is not covered by this claim; it is the subject of the accepted claim [[problems/polynomials/E0116/claims/2025_03_24_krishnapur_lundberg_ramachandran|Krishnapur, Lundberg and Ramachandran 2025]].

Depends on. No page of this wiki: the proof is self-contained in the paper.

Acceptance. Refereed: the paper appeared in the Michigan Mathematical Journal in 1961 (volume 8, issue 2; the issue carries no month, so the page's date is the first day of the publication year). Reviewed: erdosproblems.com labels the problem proved and states that the lower bound ≫n−4\gg n^{-4} follows from this paper, cited as [Po61] (page last edited 2025-10-24), which the corpus counts as documented independent acceptance by the site's curator, T. F. Bloom (erdosproblems.com); the community database lists the problem as proved with a Lean marker (entry last updated 2026-08-24).

Formalization. The site's Lean marker refers to a formal proof by others, with a different argument: the file linked above, in the lean-proofs repository at the pinned commit, ends with Erdos116.erdos_116, which states that there are c>0c>0 and C∈NC\in\mathbb N with ∣{z:∣∏i(z−ai)∣<1}∣>c n−C\lvert\{z:\lvert\prod_i(z-a_i)\rvert<1\}\rvert>c\,n^{-C} for every n>0n>0 and every aa with all ∣ai∣≤1\lvert a_i\rvert\le1, obtained with the explicit constants c=π/231c=\pi/2^{31} and C=14C=14; its docstring describes an elementary reflected-polynomial and finite-Fourier argument rather than Pommerenke's, and its header names Codex and GPT-5.6 Sol as formal authors and Christian Pommerenke, this paper's author, as the informal author, which is why the file is a link on this page and not a claim of its own. The formal-conjectures statement of the problem is marked solved with a link to this declaration. The development is unbuilt and unaudited against the question by this corpus, so the evidence lists no formalized kind; the standing rests on the refereeing and the site's acceptance.