Young tableau(x)

Tags: #definition

Young tableau(x)

Given a Young diagram (ex: (3, 3, 2, 1, 1))
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We call a tableau(x) on a Young diagram a numbering of the boxes 1 through some d.

The standard Young tableaux (SYT) is a tableaux that uses the numbers 1 through n (the weight of the partition) that fills the rows where each box is increasing as you go down and right.

ex:
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(but it doesn't have to be in reading order)

We use fλ to denote the number of standard Young tableaus of size λ

Properties

The hook length formula $$
f_\lambda = \frac{n!}{\prod_{b \in \lambda} h(b)}

where $h(b)$ is the hook length of the box $b$. - $n! = \sum_{\lambda \vdash n} (f_\lambda)^2$ where $f_\lambda$ is the number of standard Young tableaus of size $\lambda$. proof here # See also $S_d$ acts on this tableau, see Young symmetrizer hook length