Cocyclic development of pairwise combinatorial designs was discovered by Warwick de Launey and Kathy Horadam in the early 1990s. We first recount some algebraic essentials of the theory. Building on this, we proceed to discuss recent new results about the cocyclic development of a certain infinite family of generalized Hadamard matrices (with connections to finite geometries, and which contain the well-known Sylvester Hadamard matrix family as a special case). Specifically, we characterise the ‘indexing groups’ of the matrices considered as cocyclic designs. Many open questions remain; we mention some of these.
This is joint work with Ronan Egan (also at National University of Ireland, Galway).
How to participate in this seminar:
1. Book your nearest ACE facility;
2. Notify Vera Roshchina at RMIT (maths.colloquia@rmit.edu.au) to notify you will be participating.
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