论文标题
在单位值多项式函数上
On the group of unit-valued polynomial functions
论文作者
论文摘要
令$ r $为有限的交换戒指,$ 1 \ ne 0 $。 $ r $上多项式函数的集合$ \ MATHCAL {F}(R)$是带有尖端操作的有限交换环。它的组$ \ Mathcal {f}(r)^\ times $只是所有单位值多项式函数的集合,这是将$ r $映射到其组单元组的一组多项式函数。我们表明,$ \ Mathcal {p} _r(r [x]/(x^2))$ ring $ r [x]/(x^2)$上的多项式排列组,由$ r $以上的$ r $代表的排列组成,在$ \ nathcal $ \ nathcal的半级产品中( $ \ Mathcal {p}(r)$ $ r $上的多项式排列组。特别是,当$ r = \ mathbb {f} _q $时,我们证明了$ \ mathcal {p} _ {\ Mathbb {f} _q}(\ Mathbb {f} _q [x] _q [x]/(x]/(x^2)) \ltimes_θ\ Mathcal {f}(\ Mathbb {f} _Q)^\ times $。此外,我们计算单位值多项式函数$ \ pmod {p^n} $,并获得这些功能的规范表示。
Let $R$ be a finite commutative ring with $1\ne 0$. The set $\mathcal{F}(R)$ of polynomial functions on $R$ is a finite commutative ring with pointwise operations. Its group of units $\mathcal{F}(R)^\times$ is just the set of all unit-valued polynomial functions, that is the set of polynomial functions which map $R$ into its group of units. We show that $\mathcal{P}_R(R[x]/(x^2))$ the group of polynomial permutations on the ring $R[x]/(x^2)$, consisting of permutations represented by polynomials over $R$, is embedded in a semidirect product of $\mathcal{F}(R)^\times$ by $\mathcal{P}(R)$ the group of polynomial permutations on $R$. In particular, when $R=\mathbb{F}_q$, we prove that $\mathcal{P}_{\mathbb{F}_q}(\mathbb{F}_q[x]/(x^2))\cong \mathcal{P}(\mathbb{F}_q) \ltimes_θ\mathcal{F}(\mathbb{F}_q)^\times$. Furthermore, we count unit-valued polynomial functions $\pmod{p^n}$ and obtain canonical representations for these functions.