摘要
Abstract A t-hyperwhesl （t 〉 3） of length l （or Wz（t） for brevity） is a t-uniform hypergraph （V, E）, where t E= {e1,e2,...,el} and vl,v2,...,vt are distinct vertices of V = Ui=1 ei such that for i= 1,...,1, vi,vi＋1 ∈ei and ei ∩ ej = P, j ∈ {i - 1, i,i ＋ 1}, where the operation on the subscripts is modulo 1 and P is a vertex of V which is different from vi, 1 〈 i 〈 l. In this paper, the minimum covering problem of MCλ（3, W（3）,v） is investigated. Direct and recursive constructions on MCλ（3, W（3）,v） are presented. The covering number cλ（3, W4（3）, v） is finally determined for any positive integers v 〉 5 and A.
Abstract A t-hyperwhesl （t 〉 3） of length l （or Wz（t） for brevity） is a t-uniform hypergraph （V, E）, where t E= {e1,e2,...,el} and vl,v2,...,vt are distinct vertices of V = Ui=1 ei such that for i= 1,...,1, vi,vi＋1 ∈ei and ei ∩ ej = P, j ∈ {i - 1, i,i ＋ 1}, where the operation on the subscripts is modulo 1 and P is a vertex of V which is different from vi, 1 〈 i 〈 l. In this paper, the minimum covering problem of MCλ（3, W（3）,v） is investigated. Direct and recursive constructions on MCλ（3, W（3）,v） are presented. The covering number cλ（3, W4（3）, v） is finally determined for any positive integers v 〉 5 and A.
基金
Supported by the National Natural Science Foundation of China (No.10771013 and 10831002)
