A priori bounds for anti-Herglotz functions with positive real parts
نویسنده
چکیده
Let f(z) be a function analytic in the complex domain C+∪C−∪(−1,+∞), real for real z and such that f(z), f2(z) are anti-Herglotz functions. In this paper we show that f(z) possesses simple upper and lower bounds given by rational functions. Our main tool is the analytic theory of continued fractions. An application to the theory of solutions of the Feigenbaum-Cvitanović equation is given.
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