Zyablov bound

The Zyablov bound is a concept in the field of combinatorial design and coding theory, particularly related to covering designs. Named after the Russian mathematician Alexander Zyablov, the bound provides a limit on the number of blocks in a covering design given certain parameters. In more formal terms, the Zyablov bound applies to the problem of covering a finite set with subsets (or blocks) such that every element of the set is contained in at least a specified number of blocks.