Addable node of a Young diagram
= Addable node of a Young diagram
{title2=$\lambda^+$}
= Addable nodes of a Young diagram
{synonym}
An addable node is a cell outside a <Young diagram> whose insertion leaves a Young diagram. Its left and upper predecessors, when present in the positive-coordinate grid, must already belong to the diagram. Different addable nodes have distinct <Young-diagram cell contents>.