Computing Hecke Eigenvalues below the Cohomological Dimension
نویسنده
چکیده
Let Γ be a neat finite-index subgroup of SLn(Z) or GLn(Z), and let ν be the cohomological dimension of Γ. We present an algorithm to compute the eigenvalues of the Hecke operators on H(Γ;Z), for n = 2, 3, and 4. In addition, we describe a modification of the modular symbol algorithm of Ash-Rudolph [9] for computing Hecke eigenvalues on H(Γ;Z).
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