COMBINATORICS
2006
13 years 4 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 4 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 4 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 4 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 4 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 4 months ago
2006
COMBINATORICS
2006
13 years 4 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 4 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 4 months ago
2006
COMBINATORICS
2006
13 years 4 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,...