Communications of the Korean Mathematical Society (대한수학회논문집)

Korean Mathematical Society (대한수학회)
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NEWFORMS OF LEVEL 4 AND OF TRIVIAL CHARACTER

  • Zhang, Yichao (Department of Mathematics University of Connecticut)
  • Received : 2014.02.28
  • Published : 2014.10.31
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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.

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References

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