Some Connections Between The Arithmetic and The Geometry of Lipschitz   Integers
  Some relationships between the arithmetic and the geometry of Lipschitz and Hurwitz integers are presented. In particular, it is shown that the (ternary) vector product of a Lipschitz integer $\alpha$ with two other Lipschitz integers, both orthogonal to $\alpha$, is a left and also a right multiple of $\alpha$, and that the vector product of two left multiples of $\alpha$ with any other Lipschitz integer is still a left multiple of $\alpha$. We also provide new arithmetical proofs for some old results of Gordon Pall, and raise a geometric problem on the location of some integral quaternions that is related to the factorization of some integers. 
Ant\'onio Machiavelo and Lu\'is Ro\c{c}adas
math.NT