设Pn和Cn是具有n个顶点的路和圈,Sn是n个顶点的的星图,nG表示n个图G的不相交并。Srp+1^G表示把星Sr+1的r个1度点分别与rG的每个分支的第i个顶点重迭后得到的图,可简记为Sδ+1^G,δ=rp;设m是自然数,图P(2m+1)+(m+1)δ^SG是表示把(m+1)Sδ+1^G的每个分支的r度顶点分别与P2m+1的下标为奇数的m+1个顶点重迭后得到的图,运用图的伴随多项式的性质,讨论了图簇PP(2 m+1)+(m+1)δ^SG∪K1(m为奇数)和P(2 m+1)+(m+1)δ^SG∪Sδ+1^G(m为偶数)的伴随多项式的因式分解式,令m=2^k-1 q-1,λk=(2^kq-1)+2^k-1 qδ,讨论了图簇Pλk^SG∪(k-1)K1和Pλk^SG的伴随多项式的因式分解式,进而证明了这些图的补图的色等价性。
Let Pnbe a path with nvertices,Cn be a cycle with n vertices,Sn be a star with n vertices,and nG be the union of ngraphs G without common vertex.It denoted by Srp+1^G the graph consisting of Sr+1 and rG by coinciding r vertices of degree 1 of S(rp+1) with the ith vertex of every component of rG,respectively,abbreviated as Sδ+1^G,δ=rp;Let m be a nature number,P(2 m+1)+(m+1)^SG δbe the graph consisting of(m+1)Sδ+1^G and P(2m+1) by coinciding the vertex of degree r of every component of (m+1)Sδ+1^G with m+1vertices whose subscripts are odd of P2 m+1,respectively.By using the properties of adjoint polynomials of graphs,it discussed the factorizations of adjoint polynomials of graphs P(2 m+1)+(m+1)δ^SG ∪ K1(where m is odd)and P(2 m+1)+(m+1)δ^SG∪Sδ+1^G(where m is even).Letting m=2^kq-1andλn=(2^nq-1)+2^n-1qδ,it discussed the factorizations of adjoint polynomials of graphs Pλk^SG∪(k-1)K1 and Pλk^SG.Furthermore,it proved the chromatic equivalence of complements of these graphs.