On contiguous congruent sets in Euclidean space

On Contiguous Congruent Sets in Euclidean Space

Contact Numbers for Congruent Sphere Packings in Euclidean 3-Space

The contact graph of an arbitrary finite packing of unit balls in Euclidean 3-space is the (simple) graph whose vertices correspond to the packing elements and whose two vertices are connected by an edge if the corresponding two packing elements touch each other. One of the most basic questions on contact graphs is to find the maximum number of edges that a contact graph of a packing of n unit ...

On distinct distances in homogeneous sets in the Euclidean space

It is shown that a homogeneous set of n points in the d-dimensional Euclidean space determines at least Ω(n2d/(d 2+1)/ log n) distinct distances for a constant c(d) > 0. In three-space, the above general bound is slightly improved and it is shown that a homogeneous set of n points determines at least Ω(n.6091) distinct distances.

On Isosceles Sets in the 4-Dimensional Euclidean Space

A subset X in the k-dimensional Euclidean space R that contains n points (elements) is called an n-point isosceles set if every triplet of points selected from them forms an isosceles triangle. In this paper, we show that there exist exactly two 11-point isosceles sets up to isomorphism and that the maximum cardinality of isosceles sets in R is 11 .

On the Quaternionic Curves in the Semi-Euclidean Space E_4_2

In this study, we investigate the semi-real quaternionic curves in the semi-Euclidean space E_4_2. Firstly, we introduce algebraic properties of semi-real quaternions. Then, we give some characterizations of semi-real quaternionic involute-evolute curves in the semi-Euclidean space E42 . Finally, we give an example illustrated with Mathematica Programme.