Enumerating topological (nk)-configurations

نویسندگان

  • Jürgen Bokowski
  • Vincent Pilaud
چکیده

An (nk)-configuration is a set of n points and n lines in the projective plane such that their point – line incidence graph is k-regular. The configuration is geometric, topological, or combinatorial depending on whether lines are considered to be straight lines, pseudolines, or just combinatorial lines. We provide an algorithm for generating, for given n and k, all topological (nk)-configurations up to combinatorial isomorphism, without enumerating first all combinatorial (nk)-configurations. We apply this algorithm to confirm efficiently a former result on topological (184)-configurations, from which we obtain a new geometric (184)-configuration. Preliminary results on (194)-configurations are also briefly reported.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

On the generation of topological (nk)-configurations

An (nk)-configuration is a set of n points and n lines in the projective plane such that the point – line incidence graph is k-regular. The configuration is geometric, topological, or combinatorial depending on whether lines are considered to be straight lines, pseudolines or just combinatorial lines. We provide an algorithm for generating all combinatorial (nk)-configurations that admit a topo...

متن کامل

On topological and geometric $(19_4)$ configurations

An (nk) configuration is a set of n points and n lines such that each point lies on k lines while each line contains k points. The configuration is geometric, topological, or combinatorial depending on whether lines are considered to be straight lines, pseudolines, or just combinatorial lines. The existence and enumeration of (nk) configurations for a given k has been subject to active research...

متن کامل

Enumeration of the non-isomorphic configurations for a reconfigurable modular robot with square-cubic-cell modules

Configuration of a reconfigurable modular system is a tough issue because the possible configurations or structures grow exponentially with the number of modules. A library of the non‐isomorphic configurations should be set up as a database for configuration design and control. In this paper, we propose a matrix‐based enumerating approach for the non‐isomorphic configurati...

متن کامل

Crystal structures as periodic graphs: the topological genome and graph databases

We call attention to methods of enumerating periodic structures and to the databases that contain them. These provide information essential to the systematic design of crystalline materials. The underlying topology is uniquely specified and identifiable from the Systre key which is thus the topological genome.

متن کامل

Enumerating Regular Mixed-Cell Configurations

By means of the Cayley Trick the problem of enumerating all regular ne mixed subdivisions is reduced to enumerating all regular triangulations. The set of all regular triangulations is well-understood thanks to the bijection with the vertices of the secondary polytope. However, since we are only interested in the conngurations of mixed cells in a mixed subdivision, we want to avoid dealing with...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Comput. Geom.

دوره 47  شماره 

صفحات  -

تاریخ انتشار 2014