{ "id": "math/0610959", "version": "v1", "published": "2006-10-31T06:07:52.000Z", "updated": "2006-10-31T06:07:52.000Z", "title": "Trace formulas and class number sums", "authors": [ "Nathan Jones" ], "comment": "21 pages", "categories": [ "math.NT" ], "abstract": "We specialize the Eichler-Selberg trace formula to obtain trace formulas for the prime-to-level Hecke action on cusp forms for certain congruence groups of arbitrary level. As a consequence, we determine the asymptotic in the prime p of the number of (weighted) SL(2,Z)-conjugation orbits of 2 by 2 matrices of determinant p whose reductions modulo N lie in a given conjugacy class in GL(2,Z/NZ). This generalizes an 1885 result of Hurwitz.", "revisions": [ { "version": "v1", "updated": "2006-10-31T06:07:52.000Z" } ], "analyses": { "subjects": [ "11R29", "11F32" ], "keywords": [ "class number sums", "eichler-selberg trace formula", "prime-to-level hecke action", "conjugacy class", "congruence groups" ], "note": { "typesetting": "TeX", "pages": 21, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2006math.....10959J" } } }