Arm of a Young-diagram cell
= Arm of a Young-diagram cell
{title2=$a_\lambda(i,j)=\lambda_i-j$}
The arm consists of the cells strictly to the right of $(i,j)$ in its row of the <Young diagram>; its length is $a_\lambda(i,j)=\lambda_i-j$. It excludes the anchor cell. At $(1,2)$ in $(3,2)$ the arm contains only $(1,3)$, so its length is one. Together with the <leg of a Young-diagram cell> and the anchor, it forms the <hook of a Young diagram>.