Symmetric functions | Integer sequences
Kostka number
In mathematics, the Kostka number Kλμ (depending on two integer partitions λ and μ) is a non-negative integer that is equal to the number of semistandard Young tableaux of shape λ and weight μ. They were introduced by the mathematician Carl Kostka in his study of symmetric functions. For example, if λ = (3, 2) and μ = (1, 1, 2, 1), the Kostka number Kλμ counts the number of ways to fill a left-aligned collection of boxes with 3 in the first row and 2 in the second row with 1 copy of the number 1, 1 copy of the number 2, 2 copies of the number 3 and 1 copy of the number 4 such that the entries increase along columns and do not decrease along rows. The three such tableaux are shown at right, and K(3, 2) (1, 1, 2, 1) = 3. (Wikipedia).
_and_weight_(1,_1,_2,_1).png?width=300)
