TY - JOUR
T1 - On the order dimension of 1-sets versus k-sets
AU - Kierstead, Henry
N1 - Funding Information:
* Research partially supported by Office of Naval Research Grant N00014-90-J-1206. E-mail address: kierstead@math.la.asu.edu.
PY - 1996
Y1 - 1996
N2 - A family F of s-subsets of [t] is a (θ, s, t)-family iff the intersection of any two distinct elements of F has cardinality less than θ. Let f(θ, s, t) be the greatest integer n such that there exists an (θ, s, t)-family of cardinality n. Let dim(1, k; n) denote the dimension of Bn(1, k), the suborder of the Boolean lattice on [n] consisting of 1-subsets and k-subsets of [n]. We use upper and lower bounds on f(θ, s, t) to derive new lower and upper bounds on dim(1, k; n). In particular we answer a question of Trotter by showing that dim(1, log n; n) = Ω(log3 n/log log n). The estimation of dim(1, log n; n) plays a critical role in the determination of the maximum dimension of an ordered set with fixed maximum degree. Previously it was only known that (log2 n/4 < dim(1, log n; n) 3 n.
AB - A family F of s-subsets of [t] is a (θ, s, t)-family iff the intersection of any two distinct elements of F has cardinality less than θ. Let f(θ, s, t) be the greatest integer n such that there exists an (θ, s, t)-family of cardinality n. Let dim(1, k; n) denote the dimension of Bn(1, k), the suborder of the Boolean lattice on [n] consisting of 1-subsets and k-subsets of [n]. We use upper and lower bounds on f(θ, s, t) to derive new lower and upper bounds on dim(1, k; n). In particular we answer a question of Trotter by showing that dim(1, log n; n) = Ω(log3 n/log log n). The estimation of dim(1, log n; n) plays a critical role in the determination of the maximum dimension of an ordered set with fixed maximum degree. Previously it was only known that (log2 n/4 < dim(1, log n; n) 3 n.
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U2 - 10.1016/S0097-3165(96)80003-3
DO - 10.1016/S0097-3165(96)80003-3
M3 - Article
AN - SCOPUS:0042479214
SN - 0097-3165
VL - 73
SP - 219
EP - 228
JO - Journal of Combinatorial Theory - Series A
JF - Journal of Combinatorial Theory - Series A
IS - 2
ER -