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تسجيل مستخدم جديدTorsions in Cohomology of $text{SL}_2(mathbb{Z})$ and Congruence of Modular Forms
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Taiwang Deng
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We describe torsion classes in the first cohomology group of $text{SL}_2(mathbb{Z})$. In particular, we obtain generalized Dicksons invariants for p-power polynomial rings. Secondly, we describe torsion classes in the zero-th homology group of $text{SL}_2(mathbb{Z})$ as a module over the torsion invariants. As application, we obtain various congruences between cuspidal forms of level one and Eisenstein series.
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