Minimum embedding of a \(P_{4}\)-design into a balanced incomplete block design of index \(\lambda \)
The problem of embedding a \(P_4\)-design of index \(\mu\) with \(v\) elements into a balanced incomplete block design of index \(\lambda\) and block size four, having \(v+w\) elements, is studied. In the case when \(\mu=1\), the minimum value of \(w\) is determined for each \(\lambda\) and \(v\), leaving only seven possible exceptions when \(\lambda=3\) and one when \(\lambda=5\).
scientific article; zbMATH DE number 5648032