Reference: OPORTHOGONAL
m ⊥ n returns True if the integers m and n are relatively prime (that is, if gcd(m, n) = 1), and False otherwise. v1 ⊥ v2 returns True if the n-dimensional vectors v1 and v2 are orthogonal w.r.t. the standard inner product of R^n (or E^n), that is if their scalar (dot) product (v1|v2) = v1⋅v2 vanishes.