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Ternary quadratic forms and half-integral weight modular forms

Published online by Cambridge University Press:  01 December 2012

Alia Hamieh*
Affiliation:
Department of Mathematics, University of British Columbia, Room 121, 1984 Mathematics Road Vancouver, British Columbia, V6T 1Z2, Canada (email: [email protected])

Abstract

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Let k be a positive integer such that k≡3 mod 4, and let N be a positive square-free integer. In this paper, we compute a basis for the two-dimensional subspace Sk/20(4N),F) of half-integral weight modular forms associated, via the Shimura correspondence, to a newform FSk−10(N)), which satisfies . This is accomplished by using a result of Waldspurger, which allows one to produce a basis for the forms that correspond to a given F via local considerations, once a form in the Kohnen space has been determined.

Type
Research Article
Copyright
© The Author(s) 2012

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