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**8**

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**2**answers

359 views

### Bracket of lyndon words?

Here is a simple question regarding the standard Lyndon basis for the free Lie Algebra. Suppose I take two lyndon words $m$ and $n$ and their standard bracketings $B(m)$ and $B(n)$ as elements in the ...

**24**

votes

**1**answer

549 views

### The BCH series in terms of Lyndon words

Recently I did some explicit computations that involved the BCH series, $\log(e^x e^y)$. Here $x$ and $y$ are non-commuting variables, and the BCH series lives in the graded completion $FL(x,y)$ of ...

**4**

votes

**1**answer

222 views

### About the term “tangential derivation” on a free Lie algebra.

Let $\mathcal{lie}_n$ be the free Lie algebra generated by $n$ elements $x_1,\ldots, x_n$. A derivation $u\in \text{Der}(\mathcal{lie}_n)$ is called tangential if there exist $a_i\in \mathcal{lie}_n, ...

**5**

votes

**2**answers

619 views

### list of Hall basis

Anyone know a place where the standard Hall basis is listed up to at lest
5 fold brackets?
and for gradedLie algebras?
The rules are clear but I'd rather not turn the crank myself.
Google search did ...

**1**

vote

**2**answers

196 views

### Invariant space of lifted Chevalley automorphisms of the tensor algebra

Question. Let $k$ be a field of characteristic $0$. Let $L$ be a $k$-vector space. Consider the subspace $S$ of $L\otimes L\otimes L\otimes L$ spanned by all tensors of the form
$\left[a,\left\lbrace ...