The Index of Determinacy for Measures and the ¿2-norm of Orthonormal Polynomials
نویسندگان
چکیده
For determinate measures ß having moments of every order we define and study an index of determinacy which checks the stability of determinacy under multiplication by even powers of \t — z\ for z a complex number. Using this index of determinacy, we solve the problem of determining for which z£C the sequence {p\T\z))n ( m 6 N ) belongs to I2 , where (p„)„ is the sequence of orthonormal polynomials associated with the measure ft.
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