NEWFORMS OF LEVEL 4 AND OF TRIVIAL CHARACTER

Title & Authors
NEWFORMS OF LEVEL 4 AND OF TRIVIAL CHARACTER
Zhang, Yichao;

Abstract
In this paper, we consider characters of $\small{SL_2(\mathbb{Z})}$ 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;
Language
English
Cited by
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