Standard skew Young tableau
= Standard skew Young tableau
A standard skew Young tableau fills the $k$ cells of a <skew Young diagram> bijectively with $1,\ldots,k$, increasing along each row and column. Equivalently it is a <linear extension of a partially ordered set> formed from the row and column inequalities. Interchanging consecutive labels preserves standardness exactly when their cells are incomparable in that partial order.