4 citations · 9 across the 8 of their papers we have counts for
5 papers · 1 filter
On nontrivial cross-2-intersecting families
Jingjun Bao, Lijun Ji, Liying Yu
Two families \(\mathcal{A}\subseteq\binom{[n]}{k}\) and \(\mathcal{B}\subseteq\binom{[n]}{\ell}\) are said to be nontrivial cross-\(t\)-intersecting if \(|A \cap B| \geq t\) for al…
The maximum product of sizes of cross-\(t\)-intersecting families
Jingjun Bao, Lijun Ji
Two families of sets \(\mathcal{A}\) and \(\mathcal{B}\) are called \emph{cross-\(t\)-intersecting} if \(|A \cap B| \geq t\) for all \(A \in \mathcal{A}\) and \(B \in \mathcal{B}\)…
New Necessary Conditions for Existence of Strong External Difference Families
Jingjun Bao, Lijun Ji
Strong external difference families (SEDFs) were introduced by Paterson and Stinson as a more restrictive version of external difference families. SEDFs can be used to produce opti…
New Existence and Nonexistence Results for Strong External Difference Families
Jingjun Bao, Lijun Ji, Ruizhong Wei +1
In this paper, we use character-theoretic techniques to give new nonexistence results for -strong external difference families (SEDFs). We also use cyclotomic classes to…
The completion of optimal -packings
Jingjun Bao, Lijun Ji
A 3- packing design consists of an -element set and a collection of -element subsets of , called {\it blocks}, such that every -element subset of is co…