The problem originated in an attempt to construct matrices A with entries 0 and 1 such that the product $AA^T$ has each entry which is off the main diagonal either 0 or 1.Such matrices are quite common and appear as the incidence matrices of finite projective and affine planes as well as the incidence matrices of configurations such as the Desargues and Pappus configurations.The configurations which we study are all self-dual.The question of whether configurations which admit a preassigned group of collineations can be constructed is also addressed
We study point-line incidence structures and their properties in the projective plane. Our motivatio...
Consider an incidence structure whose points are the points of a PGn(n + 2,q) and whose block are th...
AbstractThe combinatorial structure configuration which was already defined as early as 1876 is the ...
In a projective plane over a field F, the diagonal points of a quadrangle are collinear if and only ...
The incidence matrices of many combinatorial structures satisfy the so called rectangular rule, i.e....
AbstractThis article deals with algorithmic and structural aspects related to the computer-aided stu...
AbstractIn non-commutative projective geometry there exist Pappus' configurations whose diagonal poi...
Decomposition into a direct sum of irreducible representations of the representation of the full col...
AbstractIn this article we show that projective planes with a small collineation group of perspectiv...
AbstractDecomposition into a direct sum of irreducible representations of the representation of the ...
Ziel dieser Arbeit ist eine computerunterstützte Suche nach, bis auf Isomorphie, allen projektiven E...
Summary. The classical sequence of implications which hold between Desargues and Pappus Axioms is pr...
We look into the rich combinatorics of fully-packed loop configurations (or FPL, or alternating-sign...
A. Lewandowski and H. Makowiecka proved in 1979 that existence of the Havlicek-Tietze configuration ...
AbstractThe question is discussed whether a configuration (vr, bk) (i.e. is a finite incidence struc...
We study point-line incidence structures and their properties in the projective plane. Our motivatio...
Consider an incidence structure whose points are the points of a PGn(n + 2,q) and whose block are th...
AbstractThe combinatorial structure configuration which was already defined as early as 1876 is the ...
In a projective plane over a field F, the diagonal points of a quadrangle are collinear if and only ...
The incidence matrices of many combinatorial structures satisfy the so called rectangular rule, i.e....
AbstractThis article deals with algorithmic and structural aspects related to the computer-aided stu...
AbstractIn non-commutative projective geometry there exist Pappus' configurations whose diagonal poi...
Decomposition into a direct sum of irreducible representations of the representation of the full col...
AbstractIn this article we show that projective planes with a small collineation group of perspectiv...
AbstractDecomposition into a direct sum of irreducible representations of the representation of the ...
Ziel dieser Arbeit ist eine computerunterstützte Suche nach, bis auf Isomorphie, allen projektiven E...
Summary. The classical sequence of implications which hold between Desargues and Pappus Axioms is pr...
We look into the rich combinatorics of fully-packed loop configurations (or FPL, or alternating-sign...
A. Lewandowski and H. Makowiecka proved in 1979 that existence of the Havlicek-Tietze configuration ...
AbstractThe question is discussed whether a configuration (vr, bk) (i.e. is a finite incidence struc...
We study point-line incidence structures and their properties in the projective plane. Our motivatio...
Consider an incidence structure whose points are the points of a PGn(n + 2,q) and whose block are th...
AbstractThe combinatorial structure configuration which was already defined as early as 1876 is the ...