Combinatorics '90 (eBook)

Front Cover 1
Combinatorics '90 Recent Trends and Applications 4
Copyright Page 5
Contents 8
Foreword 6
Chapter 1. Irregular assignments and vertex-distinguishing edge-colorings of graphs 12
Chapter 2. Construction of non-isomorphic regular tournaments 22
Chapter 3. On structures T(t, q , r , n) 36
Chapter 4. A tactical decomposition for incidence structures 48
Chapter 5. Note on a characterization of Segre variety in PG(r, q ) 56
Chapter 6. A property of sharply 3-transitive finite permutation sets 60
Chapter 7. Faithful orbits in symmetric designs 72
Chapter 8. Minimal flagtransitive geometries 80
Chapter 9. Some results on hyperarchimedean MV-algebras 82
Chapter 10. Three combinatorial sequences derivable from the lattice path counting 92
Chapter 11. Compound closed chains in circular planar nearrings 104
Chapter 12. p-primitive semifield planes 118
Chapter 13. The fractal-like Steiner triple system 130
Chapter 14. Locally partial geometries with different types of residues 138
Chapter 15. (0, n)-sets in a generalized quadrangle 150
Chapter 16. Combinatorics and cryptography 170
Chapter 17. Recent intrinsic characterizations of ovoids and elliptic quadrics in PG(3, K) 186
Chapter 18. A natural association of PGL(V)-orbits in the Segre variety (P(V))m with flags and Young tableaux 202
Chapter 19. Decomposing Steiner triple systems into four-line configurations 226
Chapter 20. Non-symmetric configurations with deficiencies 1 and 2 238
Chapter 21. Characterizing Linear spaces by blocking sets 252
Chapter 22. Partial geometries of rank n 260
Chapter 23. The minimal parabolic geometry of the Conway group Co1 is simply connected 270
Chapter 24. Coset enumeration in groups and constructions of symmetric designs 286
Chapter 25. On the ubiquity of Denniston-type translation ovals in generalized André planes 290
Chapter 26. Translation planes and related combinatorial structures 308
Chapter 27. Finite reflection groups and their corresponding structures 328
Chapter 28. On nonisomorphic BIBD with identical parameters 348
Chapter 29. Incidence loops and their geometry 358
Chapter 30. Families of Menon difference sets 376
Chapter 31. On the characterization problem for finite linear spaces 392
Chapter 32. Linear spaces in which every line of maximal degree meets only few lines 402
Chapter 33. Flag-transitive Buekenhout geometries 414
Chapter 34. Collineations of the generalized quadrangles associated with q-clans 460
Chapter 35. Projective embedding of fibered groups and the Suzuki groups 474
Chapter 36. Codes, block designs, Frobenius groups and new-rings 482
Chapter 37. The flag-transitive affine planes of order 27 488
Chapter 38. Symmetric functions and bijective identities 512
Chapter 39. On the existence of nearly Kirkman systems 522
Chapter 40. Codes and semilinear spaces 530
Chapter 41. Old and new results on spreads and ovoids of finite classical polar spaces 540
Chapter 42. Large partial parallel classes in Steiner systems 556
Chapter 43. Minimal line distinguishing colourings in graphs 560
Chapter 44. Some results on –1 multiplier of difference lists 570