COMBINATORICS
2000
13 years 4 months ago
2000
Let fr n(k) be the number of 132-avoiding permutations on n letters that contain exactly r occurrences of 12 . . . k, and let Fr(x; k) and F (x, y; k) be the generating functions d...
COMBINATORICS
2000
13 years 4 months ago
2000
We find a generating function expressed as a continued fraction that enumerates ordered trees by the number of vertices at different levels. Several Catalan problems are mapped to...
COMBINATORICS
2000
13 years 4 months ago
2000
COMBINATORICS
2000
13 years 4 months ago
2000
We define a number of new combinatorial operations on skew semistandard domino tableaux that complement constructions defined by C. Carr
COMBINATORICS
2000
13 years 4 months ago
2000
We describe matrices whose determinants are the Jack polynomials expanded in terms of the monomial basis. The top row of such a matrix is a list of monomial functions, the entries...
COMBINATORICS
2000
13 years 4 months ago
2000
In this paper, explicit formulae for the expectation and the variance of descent functions on random standard Young tableaux are presented. Using these, it is shown that the norma...
COMBINATORICS
2000
13 years 4 months ago
2000
COMBINATORICS
2000
13 years 4 months ago
2000
The question of whether the characteristic polynomial of a simple graph is uniquely determined by the characteristic polynomials of its vertex-deleted subgraphs is one of the many...
COMBINATORICS
2000
13 years 4 months ago
2000
A mixed hypergraph is a triple H = (V, C, D) where V is the vertex set and C and D are families of subsets of V , the C-edges and D-edges, respectively. A k-colouring of H is a ma...
COMBINATORICS
2000
13 years 4 months ago
2000
We examine n