For any graph H, the function h,. defined by setting h,(G) equal to the number of homomorphisms from G into H, is a multiplicative increasing function. L.ov&sz [2] has asked whether ail nonzero multiplicative increasing functions are generated by functions of this type. We show that this is not the
A class of additive multiplicative graph functions
โ Scribed by Lih-Hsing Hsu; Chiuyuan Chen; En-Yih Jean
- Publisher
- Elsevier Science
- Year
- 1987
- Tongue
- English
- Weight
- 650 KB
- Volume
- 65
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
โฆ Synopsis
For a fixed graph G, the capacity function for G, Po, is defined by Pc(H)= lim,__,ยฎ[yo(H')] TM, where y6(H) is the maximum number of disjoint G's in H. In , Hsu proved that Pr2 can be viewed as a lower bound for multiplicative increasing graph functions. But it was not known whether Pr2 is multiplicative or not. In this paper, we prove that Pc is multiplicative and additive for some graphs G which include K2. Some properties of Pc are also discussed in this paper.
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