Departments of Mathematics and Physics, University of Arizona, Tucson, Arizona 85721
Abstract:
A machine-generated list of local solutions of the Heun equation is given. They are analogous to Kummer's solutions of the Gauss hypergeometric equation, since the two equations are canonical Fuchsian differential equations on the Riemann sphere with four and three singular points, respectively. Tabulation is facilitated by the identification of the automorphism group of the equation with singular points as the Coxeter group . Each of the expressions is labeled by an element of . Of the , are equivalent expressions for the local Heun function , and it is shown that the resulting order- group of transformations of is isomorphic to the symmetric group . The isomorphism encodes each transformation as a permutation of an abstract four-element set, not identical to the set of singular points.