# All Questions

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### Sum of Stirling numbers with exponents

I have a trouble with the following sum $\sum_{i=0}^n\binom{n}{i}S(i,m)3^i$, where $S(i,m)$ is the Stirling number of the second kind (the number of all partitions of $i$ elements into $m$ nonempty ...
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### Which weighted projective spaces (and their finite quotients) are local complete intersections?

Let $G$ be a finite subgroup of $Gl_{n+1}(k)$ (for $k$ being an algebraically closed field). My question is: do there exist examples of $G$ such that the corresponding quotient $P$ of $\mathbb{P}^n$ ...
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### Anisotropic limit of a Dirac delta function

I hope this is the right place for this question, sorry if it is not. As part of a fairly long equation which I will not bore you with I have a Dirac delta function $\delta({k}-{k}_1-{k}_2)$ where the ...
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### fundamental groups of $SO(n)$ and $Sp(2n)$

Let $k$ be an algebraically closed field of characteristic zero. and let $$\sigma: SL_n(k)\rightarrow SL_n(k)$$ be an involution. My questions are: How could one calculate the fundamental group of ...
Let $K$ be a compact Lie group. Let $C_K$ denote the category whose objects are the compact lie groups containing $K$ and whose morphisms are inclusion of the groups. Let $Y$ be a $K-$space such that ...