Semistandard Young tableau
= Semistandard Young tableau
A semistandard Young tableau fills a <Young diagram> with positive <integers>, permitting repeated entries, so that entries weakly increase along rows and strictly increase down columns. Its content records the number of occurrences of each entry. The <Kostka number> $K_{\lambda\mu}$ counts such fillings of shape $\lambda$ and content $\mu$.