Symmetry of a group divisible design with r=λ1+1

2002 ◽  
Vol 106 (1-2) ◽  
pp. 31-37
Author(s):  
Tsutomu Shimata ◽  
Sanpei Kageyama
2015 ◽  
pp. 65-88
Author(s):  
Premadhis Das ◽  
Ganesh Dutta ◽  
Nripes Kumar Mandal ◽  
Bikas Kumar Sinha

1982 ◽  
Vol 34 (2) ◽  
pp. 257-297 ◽  
Author(s):  
Dieter Jungnickel

A (group) divisible design is a tactical configuration for which the v points are split into m classes of n each, such that points have joining number λ (resp. λ2) if and only if they are in the same (resp. in different) classes. We are interested in such designs with a nice automorphism group. We first investigate divisible designs with equally many points and blocks admitting an automorphism group acting regularly on all points and on all blocks, i.e., with a Singer group (Singer [50] obtained the first result in this direction for the finite projective spaces).As in the case of block designs, one may expect a divisible design with a Singer group to be equivalent to some sort of difference set; as it turns out, one here obtains a generalisation of the relative difference sets of Butson and Elliott [11] and [20].


2016 ◽  
Vol 4 (2) ◽  
pp. 161-175
Author(s):  
Jyoti Sharma ◽  
Jagdish Prasad ◽  
D. K. Ghosh

1982 ◽  
Vol 31 (1-2) ◽  
pp. 53-62
Author(s):  
Sanjeev C. Panandikar

In this paper we discuss some of the properties of the matrix ( NN') of the Generalised Group Divisible (GGD) design with λ ij ; i, j=l,2. The properties are the characteristic roots, the Hasse­Minkowski invariant and the nonexistence theorems. Some new methods for constructing GGD designs are also given.


1975 ◽  
Vol 3 (2) ◽  
pp. 285-288
Author(s):  
H. T. Trivedi ◽  
V. K. Sharma

Sign in / Sign up

Export Citation Format

Share Document