All Questions

In "Four examples of Beilinson-Bernstein localization", Anna Romanov introduces the basis $m_k = \frac{(-1)^k}{k!} \partial^k \delta $ on p. 9, where $\partial$ is a partial derivative and $\...

Let $D_{n}$ denotes the dihedral group of order $2n$. Firstly, for self-referencing of the question, I give some definitions which are standard. Let $G$ be a finite group. A subset $S$ of group $G$ ...

Suppose $X\subset \mathbb S^1$ is a finite subset of the group $\mathbb S^1$ such that $|X+X|<(1+c )|X|$ for a sufficiently small $c\in(0,1)$. I believe that in such case there exists a subgroup $G=...

The cycle index (polynomial) of the symmetric group $\mathfrak{S}_n$ is given by the formula: $$Z(\mathfrak{S}_n)(x_1,\dots,x_n)=\sum_{1j_1+2j_2+\cdots+nj_n=n}\prod_{k=1}^n\frac{x_k^{j_k}}{k^{j_k}j_k!}...