A note on the independent domination number of subset graph

Xue-Gang Chen; De-xiang Ma; Hua Ming Xing; Liang Sun

Czechoslovak Mathematical Journal (2005)

  • Volume: 55, Issue: 2, page 511-517
  • ISSN: 0011-4642

Abstract

top
The independent domination number i ( G ) (independent number β ( G ) ) is the minimum (maximum) cardinality among all maximal independent sets of G . Haviland (1995) conjectured that any connected regular graph G of order n and degree δ 1 2 n satisfies i ( G ) 2 n 3 δ 1 2 δ . For 1 k l m , the subset graph S m ( k , l ) is the bipartite graph whose vertices are the k - and l -subsets of an m element ground set where two vertices are adjacent if and only if one subset is contained in the other. In this paper, we give a sharp upper bound for i ( S m ( k , l ) ) and prove that if k + l = m then Haviland’s conjecture holds for the subset graph S m ( k , l ) . Furthermore, we give the exact value of β ( S m ( k , l ) ) .

How to cite

top

Chen, Xue-Gang, et al. "A note on the independent domination number of subset graph." Czechoslovak Mathematical Journal 55.2 (2005): 511-517. <http://eudml.org/doc/30965>.

@article{Chen2005,
abstract = {The independent domination number $i(G)$ (independent number $\beta (G)$) is the minimum (maximum) cardinality among all maximal independent sets of $G$. Haviland (1995) conjectured that any connected regular graph $G$ of order $n$ and degree $\delta \le \frac\{1\}\{2\}\{n\}$ satisfies $i(G)\le \lceil \frac\{2n\}\{3\delta \}\rceil \frac\{1\}\{2\}\{\delta \}$. For $1\le k\le l\le m$, the subset graph $S_\{m\}(k,l)$ is the bipartite graph whose vertices are the $k$- and $l$-subsets of an $m$ element ground set where two vertices are adjacent if and only if one subset is contained in the other. In this paper, we give a sharp upper bound for $i(S_\{m\}(k,l))$ and prove that if $k+l=m$ then Haviland’s conjecture holds for the subset graph $S_\{m\}(k,l)$. Furthermore, we give the exact value of $\beta (S_\{m\}(k,l))$.},
author = {Chen, Xue-Gang, Ma, De-xiang, Xing, Hua Ming, Sun, Liang},
journal = {Czechoslovak Mathematical Journal},
keywords = {independent domination number; independent number; subset graph; independent domination number; independent number; subset graph},
language = {eng},
number = {2},
pages = {511-517},
publisher = {Institute of Mathematics, Academy of Sciences of the Czech Republic},
title = {A note on the independent domination number of subset graph},
url = {http://eudml.org/doc/30965},
volume = {55},
year = {2005},
}

TY - JOUR
AU - Chen, Xue-Gang
AU - Ma, De-xiang
AU - Xing, Hua Ming
AU - Sun, Liang
TI - A note on the independent domination number of subset graph
JO - Czechoslovak Mathematical Journal
PY - 2005
PB - Institute of Mathematics, Academy of Sciences of the Czech Republic
VL - 55
IS - 2
SP - 511
EP - 517
AB - The independent domination number $i(G)$ (independent number $\beta (G)$) is the minimum (maximum) cardinality among all maximal independent sets of $G$. Haviland (1995) conjectured that any connected regular graph $G$ of order $n$ and degree $\delta \le \frac{1}{2}{n}$ satisfies $i(G)\le \lceil \frac{2n}{3\delta }\rceil \frac{1}{2}{\delta }$. For $1\le k\le l\le m$, the subset graph $S_{m}(k,l)$ is the bipartite graph whose vertices are the $k$- and $l$-subsets of an $m$ element ground set where two vertices are adjacent if and only if one subset is contained in the other. In this paper, we give a sharp upper bound for $i(S_{m}(k,l))$ and prove that if $k+l=m$ then Haviland’s conjecture holds for the subset graph $S_{m}(k,l)$. Furthermore, we give the exact value of $\beta (S_{m}(k,l))$.
LA - eng
KW - independent domination number; independent number; subset graph; independent domination number; independent number; subset graph
UR - http://eudml.org/doc/30965
ER -

References

top
  1. Independence graphs, Proc. 5th Southeast Conf. Comb. Graph Theor. Comput, Utilitas Math., Boca Raton, 1974, pp. 471–491. (1974) MR0357174
  2. 10.1016/0012-365X(88)90076-3, Discrete Math. 70 (1988), 17–20. (1988) MR0943719DOI10.1016/0012-365X(88)90076-3
  3. 10.1016/0012-365X(91)90318-V, Discrete Math. 94 (1991), 95–101. (1991) Zbl0758.05061MR1139586DOI10.1016/0012-365X(91)90318-V
  4. 10.1016/0012-365X(94)00022-B, Discrete Math. 143 (1995), 275–280. (1995) Zbl0838.05065MR1344759DOI10.1016/0012-365X(94)00022-B
  5. 10.1016/0012-365X(96)00025-8, Discrete Math. 158 (1996), 87–98. (1996) MR1411112DOI10.1016/0012-365X(96)00025-8
  6. 10.1016/0012-365X(81)90268-5, Discrete Math. 33 (1981), 249–258. (1981) MR0602041DOI10.1016/0012-365X(81)90268-5
  7. 10.1016/S0012-365X(98)00350-1, Discrete Math. 202 (1999), 135–144. (1999) MR1694509DOI10.1016/S0012-365X(98)00350-1

NotesEmbed ?

top

You must be logged in to post comments.