We show that the coefficients of rational $2$-functions are contained in an abelian number field. More precisely, we show that the poles of such functions are poles of order one and given by roots of unity and rational residue.

中文翻译：

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合理的 $2$-函数是阿贝尔函数

我们表明有理 $2$-函数的系数包含在阿贝尔数域中。更准确地说，我们证明这些函数的极点是一阶极点，由统一根和有理余数给出。