COMBINATORICS
1998
14 years 2 months ago
1998
COMBINATORICS
1998
14 years 2 months ago
1998
The permanent-determinant method and its generalization, the HafnianPfaffian method, are methods to enumerate perfect matchings of plane graphs that were discovered by P. W. Kaste...
COMBINATORICS
1998
14 years 2 months ago
1998
COMBINATORICS
1998
14 years 2 months ago
1998
New lower bounds for 15 classical Ramsey numbers are established. Several of the colorings are found using a new variation of local search heuristics. Several others are found usi...
COMBINATORICS
1998
14 years 2 months ago
1998
An elementary construction using binary codes gives new record kissing numbers in dimensions from 32 to 128.
COMBINATORICS
1998
14 years 2 months ago
1998
Based on a recent improvement of the inclusion-exclusion principle, we present a new approach to network reliability problems. In particular, we give a new proof of a result of Sh...
COMBINATORICS
1998
14 years 2 months ago
1998
The paper gives a matrix-free presentation of the correspondence between full-length linear codes and projective multisets. It generalizes the BrouwerVan Eupen construction that t...
COMBINATORICS
1998
14 years 2 months ago
1998
The Galois number Gn(q) is defined to be the number of subspaces of the n-dimensional vector space over the finite field GF(q). When q is prime, we prove that Gn(q) is equal to...
COMBINATORICS
1998
14 years 2 months ago
1998
: Following Frankl and F¨uredi [1] we say a family, F, of subsets of an n-set is weakly union-free if F does not contain four distinct sets A, B, C, D with A ∪ B = C ∪ D. If i...
COMBINATORICS
1998
14 years 2 months ago
1998
The aim of this paper is to give a coherent account of the problem of constructing cubic graphs with large girth. There is a well-defined integer µ0(g), the smallest number of v...