Supported by FRG, Hong Kong Baptist-University; the first author is supported by National Natural Science Foundation of China (Grant No. 10671061) The authors would like to thank the anonymous referee for a number of helpful suggestions.
The critical group C(G) of a graph G is a refinement of the number of spanning trees of the graph and is closely connected with the Laplacian matrix. Let r(G) be the minimum number of generators (i.e., the rank)...
supported by Natural Science Foundation of Beijing (Grant No.1092002);Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of Beijing Municipality;National Natural Science Foundation of China (Grant No.10671061)
We give a concept of quasi-entwining structure,and investigate the Hochschild cohomology of the quasi-entwining structure.We obtain the equivalent theorems on the Hochschild cohomology of the quasientwining structure....