134 search results - page 19 / 27 » Combinatorics of diagrams of permutations |
COMBINATORICS
2002
13 years 9 months ago
2002
A fork stack is a generalised stack which allows pushes and pops of several items at a time. We consider the problem of determining which input streams can be sorted using a singl...
COMBINATORICS
2006
13 years 9 months ago
2006
This note contains two results on the distribution of k-crossings and k-nestings in graphs. On the positive side, we exhibit a class of graphs for which there are as many k-noncro...
CPM
2009
Springer
14 years 4 months ago
2009
Springer
A sequence of reversals that takes a signed permutation to the identity is perfect if it preserves all common intervals between the permutation and the identity. The problem of com...
JCT
2010
13 years 8 months ago
2010
Abstract. We present bijections between four classes of combinatorial objects. Two of them, the class of unlabeled (2 + 2)-free posets and a certain class of involutions (or chord ...
CPM
2004
Springer
14 years 1 months ago
2004
Springer
The problem of sorting a signed permutation by reversals is inspired by genome rearrangements in computational molecular biology. Given two genomes represented as two signed permut...