A noninereasing sequence π of n nonnegative integers graphical is graphical if it is the degree sequence of some simple graph G of order n. All graphical sequences of length n with even sum 2m and trace f forms a pos...A noninereasing sequence π of n nonnegative integers graphical is graphical if it is the degree sequence of some simple graph G of order n. All graphical sequences of length n with even sum 2m and trace f forms a poset Gn, m,f under majoriztion relation. In this paper, we characterizc the minimal elememts in Gn, m, f and determine the numbers of minimal elememts in various posers of graphical sequences.展开更多
基金Supported by a Grant-in-Aid for Scientific Research from Nanjing University of Science and Technology(No.AB96137)apartially by the National Natural Science Foundation of China(No.10471063)
文摘A noninereasing sequence π of n nonnegative integers graphical is graphical if it is the degree sequence of some simple graph G of order n. All graphical sequences of length n with even sum 2m and trace f forms a poset Gn, m,f under majoriztion relation. In this paper, we characterizc the minimal elememts in Gn, m, f and determine the numbers of minimal elememts in various posers of graphical sequences.
