The function f with property f ( λ x ) = λ p f ( x ) , x ∈ R n , λ ∈ R , p ∈ N ∗ . {\displaystyle f(\lambda \mathbf {x} )=\lambda ^{p}f(\mathbf {x} ),\quad \mathbf {x} \in \mathbb {R} ^{n},\quad \lambda \in \mathbb {R} ,\quad p\in \mathbb {N} ^{*}.}
