-biregular rings
-Amalgams IV
-Amalgams V
-Amalgams VI
-Amalgams VII
designs obtained from affine planes
The simple incidence structure formed by points and unordered pairs of distinct parallel lines of a finite affine plane of order is a design. If , is the complementary design of . If , is isomorphic to the geometric design (see [2; Theorem 1.2]). In this paper we give necessary and sufficient conditions for a design to be of the form for some finite affine plane of order . As a consequence we obtain a characterization of small designs .
24 self-inscribed decagons in Desargues configuration
2-blocking sets in PG(4, ), square.
2-transitiv abstract ovals of odd order.
4-dimensionale Translationsebenen.
4-dimensionale Translationsebenen mit 7-dimensionaler Kollineationsgruppe.
4-dimensionale Translationsebenen mit kommutativer Standgruppe.
types of configurations of flexes and sextactic points of a cubic
A characterization of the Grassmannian of points and lines for -buildings.
A characterization of the Hall planes by planar and nonplanar involutions.
A class of Buekenhout unitals in the Hall plane.
A class of complete arcs in multiply derived planes.
A Class of Translation Planes of Order 3...
A classification of finite homogeneous semilinear spaces.
A combinatorial approach to the known projective planes of order nine
A combinatorial characterization of finite projective planes using strongly canonical forms of incidence matrices is presented. The corresponding constructions are applied to known projective planes of order 9. As a result a new description of the Hughes plane of order nine is obtained.