Combinatorics '90: Recent Trends and Applications: Proceedings of the Conference on Combinatorics, Gaeta, Italy, 20-27 May, 1990 (Annals of Discrete Mathematics)

This volume forms a valuable source of information on recent developments in research in combinatorics, with special regard to the geometric point of view. Topics covered include: finite geometries (arcs, caps, special varieties in a Galois space; generalized quadrangles; Benz planes; foundation of geometry), partial geometries, Buekenhout geometries, transitive permutation sets, flat-transitive geometries, design theory, finite groups, near-rings and semifields, MV-algebras, coding theory, cryptography and graph theory in its geometric and design aspects. Front Cover Combinatorics '90 Recent Trends and Applications Copyright Page Contents Foreword Chapter 1. Irregular assignments and vertex-distinguishing edge-colorings of graphs Chapter 2. Construction of non-isomorphic regular tournaments Chapter 3. On structures T(t, q , r , n) Chapter 4. A tactical decomposition for incidence structures Chapter 5. Note on a characterization of Segre variety in PG(r, q ) Chapter 6. A property of sharply 3-transitive finite permutation sets Chapter 7. Faithful orbits in symmetric designs Chapter 8. Minimal flagtransitive geometries Chapter 9. Some results on hyperarchimedean MV-algebras Chapter 10. Three combinatorial sequences derivable from the lattice path counting Chapter 11. Compound closed chains in circular planar nearrings Chapter 12. p-primitive semifield planes Chapter 13. The fractal-like Steiner triple system Chapter 14. Locally partial geometries with different types of residues Chapter 15. (0, n)-sets in a generalized quadrangle Chapter 16. Combinatorics and cryptography Chapter 17. Recent intrinsic characterizations of ovoids and elliptic quadrics in PG(3, K) Chapter 18. A natural association of PGL(V)-orbits in the Segre variety (P(V))m with flags and Young tableaux Chapter 19. Decomposing Steiner triple systems into four-line configurations Chapter 20. Non-symmetric configurations with deficiencies 1 and 2 Chapter 21. Characterizing Linear spaces by blocking sets Chapter 22. Partial geometries of rank n Chapter 23. The minimal parabolic geometry of the Conway group Co1 is simply connected Chapter 24. Coset enumeration in groups and constructions of symmetric designs Chapter 25. On the ubiquity of Denniston-type translation ovals in generalized André planes Chapter 26. Translation planes and related combinatorial structures Chapter 27. Finite reflection groups and their corresponding structures Chapter 28. On nonisomorphic BIBD with identical parameters Chapter 29. Incidence loops and their geometry Chapter 30. Families of Menon difference sets Chapter 31. On the characterization problem for finite linear spaces Chapter 32. Linear spaces in which every line of maximal degree meets only few lines Chapter 33. Flag-transitive Buekenhout geometries Chapter 34. Collineations of the generalized quadrangles associated with q-clans Chapter 35. Projective embedding of fibered groups and the Suzuki groups Chapter 36. Codes, block designs, Frobenius groups and new-rings Chapter 37. The flag-transitive affine planes of order 27 Chapter 38. Symmetric functions and bijective identities Chapter 39. On the existence of nearly Kirkman systems Chapter 40. Codes and semilinear spaces Chapter 41. Old and new results on spreads and ovoids of finite classical polar spaces Chapter 42. Large partial parallel classes in Steiner systems Chapter 43. Minimal line distinguishing colourings in graphs Chapter 44. Some results on –1 multiplier of difference lists