The existence of 3 pairwise additive \(B(v, 2,1)\) for any \( v\geq 6\)

K. Matsubara1, S. Kageyama2
1Graduate School of Science, Hiroshima University Higashi-Hiroshima 739-8526, Japan
2Hiroshima Institute of Technology, Hiroshima 731-5193, Japan

Abstract

The existence of additive BIB designs and 2 pairwise additive BIB designs has been discussed with direct and recursive constructions in [6, 9]. In this paper, by reorganizing some methods of constructing pairwise additive BIB designs from other combinatorial structures, it is shown that 3 pairwise additive \( B(v, 2, 1) \) can be constructed for any integer \( v \geq 6 \).

Keywords: incidence matrix; balanced incomplete block (BIB) design; pairwise additive BIB design; nested BIB design; self-orthogonal latin square.