The monochromatic block number
نویسنده
چکیده
In 1993 Voloshin introduced the concept of mixed hypergraph. A mixed hypergraph is characterised by the fact that it possesses anti-edges as well as edges. In a colouring of a mixed hypergraph, every anti-edge has at least two vertices of the same colour. In this paper a new parameter is introduced: the monochromatic block number mb. It is the number of monochromatic blocks in a colouring of a Steiner system. The exact value of mb is given for every colouring in STS(v). Upper and lower bounds for mb in particular SQSs are found.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 165-166 شماره
صفحات -
تاریخ انتشار 1997