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http://dx.doi.org/10.4134/CKMS.2014.29.4.497

NEWFORMS OF LEVEL 4 AND OF TRIVIAL CHARACTER  

Zhang, Yichao (Department of Mathematics University of Connecticut)
Publication Information
Communications of the Korean Mathematical Society / v.29, no.4, 2014 , pp. 497-503 More about this Journal
Abstract
In this paper, we consider characters of $SL_2(\mathbb{Z})$ and then apply them to newforms of integral weight, level 4 and of trivial character. More precisely, we prove that all of them are actually level 1 forms of some nontrivial character. As a byproduct, we prove that they all are eigenfunctions of the Fricke involution with eigenvalue -1.
Keywords
Fricke involution; non-Dirichlet character;
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