Goodman's conjecture

{{No footnotes|date=August 2022}}

Goodman's conjecture on the coefficients of multivalued functions was proposed in complex analysis in 1948 by Adolph Winkler Goodman, an American mathematician.

Formulation

Let f(z)= \sum_{n=1}^{\infty}{b_n z^n} be a p-valent function. The conjecture claims the following coefficients hold:

|b_n| \le \sum_{k=1}^{p} \frac{2k(n+p)!}{(p-k)!(p+k)!(n-p-1)!(n^2-k^2)}|b_k|

Partial results

It's known that when p=2,3, the conjecture is true for functions of the form P \circ \phi where P is a polynomial and \phi is univalent.

External sources

  • {{cite journal |doi=10.1090/S0002-9947-1948-0023910-X|title=On some determinants related to 𝑝-valent functions |year=1948 |last1=Goodman |first1=A. W. |journal=Transactions of the American Mathematical Society |volume=63 |pages=175–192 |doi-access=free }}
  • {{cite journal |doi=10.1090/S0002-9939-1978-0460619-7|title=Goodman's conjecture and the coefficients of univalent functions |year=1978 |last1=Lyzzaik |first1=Abdallah |last2=Styer |first2=David |journal=Proceedings of the American Mathematical Society |volume=69 |pages=111–114 |doi-access=free }}
  • {{cite book |doi=10.1016/S1874-5709(02)80012-9 |chapter=Logarithmic Geometry, Exponentiation, and Coefficient Bounds in the Theory of Univalent Functions and Nonoverlapping Domains |title=Geometric Function Theory |series=Handbook of Complex Analysis |year=2002 |last1=Grinshpan |first1=Arcadii Z. |volume=1 |pages=273–332 |isbn=978-0-444-82845-3| url={{Google books|Wd7hKzGf9E8C|page=321|plainurl=yes}}}}
  • {{cite journal |last1=AGrinshpan |first1=A.Z.|title=On the Goodman conjecture and related functions of several complex variables |journal=Department of Mathematics, University of South Florida, Tampa, FL |date=1997 |volume=9 |issue=3 |pages=198–204|url=http://m.mathnet.ru/php/getFT.phtml?jrnid=aa&paperid=788&what=fullt&option_lang=eng|mr=1466800}}
  • {{cite journal |doi=10.1090/S0002-9939-1995-1242085-7|title=On an identity related to multivalent functions |year=1995 |last1=Grinshpan |first1=A. Z. |journal=Proceedings of the American Mathematical Society |volume=123 |issue=4 |page=1199 |doi-access=free }}

Category:Complex analysis

Category:Conjectures