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Goldberg 1978 counting functions sequences points entire functions

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theorem: Gol'dberg's theorem that some entire function f has, for all distinct complex a and b, upper limit infinity and lower limit zero of n(r,a)/n(r,b), together with an upper limit infinity of n(r,a,f)/A(r,f) for every complex a and a sequence r_k along which that ratio tends to zero for every complex a, uniformly on bounded domains.


Gol'dberg, A. A., Counting functions of sequences of a-points for entire functions (Russian). Sibirsk. Mat. Zh. 19 (1978), no. 1, 28--36, 236.

In Russian. Nevanlinna theory gives N(r,a) ~ T(r,f) for all a outside a small exceptional set, so lim N(r,a)/N(r,b) = 1 for all a, b outside that set. Gol'dberg shows that the analog fails completely for the unintegrated counting functions n(r,a): he constructs an entire f such that for all a, b in C with a not equal b, one has limsup n(r,a)/n(r,b) = infinity and liminf n(r,a)/n(r,b) = 0 (formula (2)), which gives an affirmative answer to a question of P. Erdos (cited as Problem 1.25 of a problem collection). The single main Theorem produces an entire f with three properties: (A) property (2) holds for all distinct a, b in C; (B) for all a in C, limsup n(r,a,f)/A(r,f) = infinity, where A(r,f) is the mean number of sheets of the Riemann surface over which the disc |z| < r is mapped; and (C) there is a sequence r_k tending to infinity with lim n(r_k,a,f)/A(r_k,f) = 0 for all a in C, uniformly for a in any bounded domain. The construction uses a family of explicit domains D(k,s,j) and D_1(k,s,j) in the finite w-plane (the s = 2 domains are discs about the origin), ordered along a sequence of triples, with the argument close in several essential points to Hayman's method. Consequences are drawn for the analogs delta_S(a) and Delta_S(a) of the Nevanlinna and Valiron deficiencies: the defect relation sum of delta_S^+(a) <= 2 holds (Shimizu; it follows from delta_S(a) <= delta(a) <= Delta(a) <= Delta_S(a) <= 1), but (B) and (C) show the analogy with the Nevanlinna and Valiron deficiencies does not extend far, through an entire f with delta_S(a) = -infinity and Delta_S(a) = 1 for every finite a in C. The paper answers Problem 1116 (Erdos's question, problem 1.25 of Hayman's 1974 collection) for entire f and finite a not equal b; p. 28 leaves the meromorphic case with a, b in the extended plane open.

Source: https://www.mathnet.ru/eng/smj6213. No notice is printed on any of the nine pages, and the hosting site's terms of use state that its materials "are fully copyrighted by Steklov Mathematical Institute, Russian Academy of Sciences, and/or by other copyright holder" and that reproduction or republication "requires written permission of the copyright holder" (https://www.mathnet.ru/php/agreement.phtml?option_lang=eng, read 2026-10-02), every other right reserved.

Bears on. #1116: property (A) of the theorem (pp. 28--29) gives an entire function with lim‾⁡r→∞n(r,a)/n(r,b)=∞\varlimsup_{r\to\infty}n(r,a)/n(r,b)=\infty and lim‾⁡r→∞n(r,a)/n(r,b)=0\varliminf_{r\to\infty}n(r,a)/n(r,b)=0 for all distinct a,b∈Ca,b\in\mathbb C, which the paper calls an affirmative answer to Erdős's question (Problem 1.25 of Hayman's 1974 list) for entire functions and finite values; the paper leaves the meromorphic case, with a,ba,b in the extended plane, open (p. 28).

Results.

  • Theorem (pp. 28--29, unnumbered): there exists an entire ff with (A) lim‾⁡n(r,a)/n(r,b)=∞\varlimsup n(r,a)/n(r,b)=\infty and lim‾⁡n(r,a)/n(r,b)=0\varliminf n(r,a)/n(r,b)=0 for all distinct a,b∈Ca,b\in\mathbb C; (B) lim‾⁡n(r,a,f)/A(r,f)=∞\varlimsup n(r,a,f)/A(r,f)=\infty for all a∈Ca\in\mathbb C; (C) a sequence rk→∞r_k\to\infty with n(rk,a,f)/A(rk,f)→0n(r_k,a,f)/A(r_k,f)\to0 for all a∈Ca\in\mathbb C, uniformly on bounded domains. The same page records the consequence (p. 29) that this ff has δS(a)=−∞\delta_S(a)=-\infty and ΔS(a)=1\Delta_S(a)=1 for every a∈Ca\in\mathbb C, while Shimizu's defect relation ∑δS+(a)≤2\sum\delta_S^+(a)\le2 still holds.

Read status: claims checked for the setting, the theorem and the consequence on pp. 28--29, read clause by clause on the page images; the proof (pp. 29--35) read for structure only. Nothing here is independently reviewed.

No file of this source is held: no license on record permits its redistribution, and the card cites the edition it names above.