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4 votes
1 answer
57 views

Exercise 8.6 of Algebraic Combinatorics by Stanley

Problem 6 in Chapter 8 of Algebraic Combinatorics by Stanley: Show that the total number of standard Young tableaux (SYT) with $n$ entries and at most two rows is ${n \choose \lfloor n/2 \rfloor}$. ...
Jonathan McDonald's user avatar
2 votes
0 answers
81 views

Restriction of induced representation over a Young subgroup and Littlewood-Richardson coefficients

I'm inexperienced in the representation theory of the symmetric group, so please correct my possible mistakes. Fix $m\leq n$, $G:=S_n$ and $H:=S_m\times S_{n-m}$ as a Young subgroup of $G$. Let $V^{\...
Jose Brox's user avatar
  • 4,886
1 vote
0 answers
49 views

Number of semi-standard Young tableaux of shape $\lambda$ with some entries fixed

Given a partition $\lambda$, the number of semi-standard Young tableaux (SSYT) of shape $\lambda$ with maximum entry $n$ is given by \begin{equation} \prod_{1\leq i<j\leq n} \frac{\lambda_i-\...
Bhargavi's user avatar
1 vote
1 answer
87 views

RSK and Matrices

It is well known that the RSK algorithm assigns to every square matrix with nonnegative integer entries a pair of semistandard Young Tableaux of same shape. The matrices are here used as just a square ...
nobody's user avatar
  • 593
2 votes
2 answers
264 views

Proof that the Lascoux-Schützenberger involutions satisfies the braid-relations

I am interested in the Lascoux-Schützenbereger involutions $\theta_i$, defined on semistandard Young tableaux. See this paper for definitions, page 4. These involutions satisfy the braid relations: (...
Joakim Uhlin's user avatar
5 votes
2 answers
384 views

$\eta$-value of a partition and its meaning

The $\eta$-value of an integer partition $\lambda = \big( \lambda_1 \geq \lambda_2 \geq \cdots \geq \lambda_k \geq 0 \big)$ is defined as \begin{equation} \eta \big( \lambda \big) \ := \ \sum_{i=1}^k ...
Jeanne Scott's user avatar
9 votes
1 answer
746 views

Young projectors in Fulton and Harris

In Section 4 of Fulton and Harris' book Representation Theory, they give the definition of a Young tableau of shape $\lambda = (\lambda_1,\dots,\lambda_k)$ and then define two subgroups of $S_d$, the ...
Alex Ortiz's user avatar
  • 25.2k
1 vote
0 answers
96 views

Murnaghan-Nakayama rule for general dimension of a hook

Let $m,r\in \mathbb{N}, n=rm$. The character of symmetric group $\chi^{\lambda}$ where $\lambda$ is of the from $(k,1^{n-k})$ evaluated at the conjugacy class of $S_{n}$ of the from $(r,\ldots,r)$, ...
GGT's user avatar
  • 1,065
2 votes
1 answer
1k views

Is there a explicit formula for the number of Semi-standard Young Tableaux over $\{1,\dots,n\}$ for a given partition $\lambda$ and a given type $\mu$

I was given an exercise to give all SSYT over $\{1,\dots,12\}$ of shape $\lambda=(4,4,3,1)$ and type $\mu=(4,2,2,2,2,0,\dots,0)$. Now I was wondering if there is an formula to say something about the ...
deavor's user avatar
  • 987
4 votes
2 answers
736 views

Reference request: Representation theory over fields of characteristic zero

Many representation theory textbooks and online resources work with the field of complex numbers or more generally algebraically closed fields of characteristic zero. I am looking for a good textbook ...
HeinrichD's user avatar
  • 2,584
9 votes
0 answers
183 views

Inequality for hook numbers in Young diagrams

Consider a Young diagram $\lambda = (\lambda_1,\ldots,\lambda_\ell)$. For a square $(i,j) \in \lambda$ define hook numbers $h_{ij} = \lambda_i + \lambda_j' -i - j +1$ and complementary hook numbers $...
Igor Pak's user avatar
  • 1,366
-1 votes
2 answers
609 views

Young tableaux of shape lambda. [closed]

Consider the partition $\lambda=(m,n-m)$ of $n$ (thus $2m \ge n$). The number of standard Young tableaux of shape $\lambda$ is given by $$f_{(m,n-m)} = \binom nm - \binom{n}{m+1}$$ a) Prove this ...
John Lennon's user avatar
  • 1,302