SFERA DI CENTRO x {\displaystyle \ {\mbox{SFERA DI CENTRO}}\ x} S ( x , r ) := { y ∈ R n : d ( x , y ) = r } {\displaystyle S(x,r):=\{y\in \mathbb {R} ^{n}:d(x,y)=r\}} INTORNO SFERICO DI x {\displaystyle \ {\mbox{INTORNO SFERICO DI}}\ x} B ( x , r ) := { y ∈ R n : d ( x , y ) < r } {\displaystyle B(x,r):=\{y\in \mathbb {R} ^{n}:d(x,y)<r\}}
ϝ : K × K ⟶ [ 0 , 1 ] n {\displaystyle \digamma :\mathbb {K} \times \mathbb {K} \longrightarrow [0,1]^{n}}
{\displaystyle }
![{\displaystyle \digamma :\mathbb {K} \times \mathbb {K} \longrightarrow [0,1]^{n}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/5ab5be70e24f6611f86e40214e75ec76c9c624e5)
