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arXiv · 2109.10551

Harder's conjecture I

Hiraku Atobe·Masataka Chida·Tomoyoshi Ibukiyama·Hidenori Katsurada·Takuya Yamauchi
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Abstract

Let $f$ be a primitive form with respect to $SL_2(Z)$. Then we propose a conjecture on the congruence between the Klingen-Eisenstein lift of the Duke-Imamoglu-Ikeda lift of $f$ and a certain lift of a vector valued Hecke eigenform with respect to $Sp_2(Z)$. This conjecture implies Harder's conjecture. We prove the above conjecture in some cases.

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Hiraku Atobe, Masataka Chida, Tomoyoshi Ibukiyama, Hidenori Katsurada, Takuya Yamauchi. 2021-09-22. Harder's conjecture I. https://arxiv.org/abs/2109.10551

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