O ct 2 00 1 CUMULANTS , LATTICE PATHS , AND ORTHOGONAL POLYNOMIALS
نویسنده
چکیده
A formula expressing free cumulants in terms of the Jacobi parameters of the corresponding orthogonal polynomials is derived. It combines Flajolet's theory of continued fractions and Lagrange inversion. For the converse we discuss Gessel-Viennot theory to express Hankel determinants in terms of various cumulants.
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