English

Packing spanning partition-connected subgraphs with small degrees

Combinatorics 2018-06-04 v1

Abstract

Let GG be a graph with XV(G)X\subseteq V(G) and let ll be an intersecting supermodular subadditive integer-valued function on subsets of V(G)V(G). The graph GG is said to be ll-partition-connected, if for every partition PP of V(G)V(G), eG(P)APl(A)l(V(G))e_G(P)\ge \sum_{A\in P} l(A)-l(V(G)), where eG(P)e_G(P) denotes the number of edges of GG joining different parts of PP. Let λ[0,1]\lambda \in [0,1] be a real number and let η\eta be a real function on XX. In this paper, we show that if GG is ll-partition-connected and for all SXS\subseteq X, Θl(GS)vS(η(v)2l(v))+l(V(G))+l(S)λ(eG(S))+l(S)),\Theta_l(G \setminus S) \le \sum_{v\in S} (\eta(v) -2l(v))+l(V(G))+l(S)-\lambda (e_G(S))+l(S)), then GG has an ll-partition-connected spanning subgraph HH such that for each vertex vXv\in X, dH(v)η(v)λl(v)d_H(v)\le \lceil \eta(v) -\lambda l(v) \rceil , where eG(S)e_G(S) denotes the number of edges of GG with both ends in SS and Θl(GS)\Theta_l(G \setminus S) denotes the maximum number of all APl(A)eGS(P)\sum_{A\in P} l(A)-e_{G\setminus S}(P) taken over all partitions PP of V(G)SV(G)\setminus S. Finally, we show that if HH is an (l1++lm)(l_1+\cdots +l_m)-partition-connected graph, then it can be decomposed into mm edge-disjoint spanning subgraphs H1,,HmH_1,\ldots, H_m such that every graph HiH_i is lil_i-partition-connected, where l1,l2,,lml_1, l_2,\ldots, l_m are mm intersecting supermodular subadditive integer-valued functions on subsets of V(H)V(H). These results generalize several known results.

Keywords

Cite

@article{arxiv.1806.00135,
  title  = {Packing spanning partition-connected subgraphs with small degrees},
  author = {Morteza Hasanvand},
  journal= {arXiv preprint arXiv:1806.00135},
  year   = {2018}
}
R2 v1 2026-06-23T02:15:30.989Z