COMBINATORICS
2006
13 years 11 months ago
2006
Abstract. Let G denote a directed graph with adjacency matrix Q and indegree matrix D. We consider the Kirchhoff matrix L = D - Q, sometimes referred to as the directed Laplacian. ...
COMBINATORICS
2006
13 years 11 months ago
2006
We completely solve the problem of enumerating combinatorially inequivalent d-dimensional polytopes with d + 3 vertices. A first solution of this problem, by Lloyd, was published ...
COMBINATORICS
2006
13 years 11 months ago
2006
Abstract. The geometric thickness of a graph G is the minimum integer k such that there is a straight line drawing of G with its edge set partitioned into k plane subgraphs. Eppste...
COMBINATORICS
2006
13 years 11 months ago
2006
We prove analogues for sub-posets of the Dowling lattices of the results of Calderbank, Hanlon, and Robinson on homology of sub-posets of the partition lattices. The technical too...
COMBINATORICS
2006
13 years 11 months ago
2006
Existing tables of constant weight codes are mainly confined to codes of length n 28. This paper presents tables of codes of lengths 29 n 63. The motivation for creating these ...
COMBINATORICS
2006
13 years 11 months ago
2006
COMBINATORICS
2006
13 years 11 months ago
2006
In the game G0 two players alternate removing positive numbers of counters from a single pile and the winner is the player who removes the last counter. On the first move of the g...
COMBINATORICS
2006
13 years 11 months ago
2006
We find the number of partitions of n whose BG-rank is j, in terms of pp(n), the number of pairs of partitions whose total number of cells is n, giving both bijective and generati...
COMBINATORICS
2006
13 years 11 months ago
2006
COMBINATORICS
2006
13 years 11 months ago
2006
With a graph G = (V, E) we associate a collection of non-negative real weights vV {i,v : 1 i m} uvE{ij,uv : 1 i j m}. We consider the probability distribution on {f : V {1,...