EJC
2010
13 years 5 months ago
2010
Four mutually dependent facts are proven.
EJC
2010
13 years 5 months ago
2010
We give a combinatorial formula for the inverses of the alternating sums of free quasi-symmetric functions of the form F(I) where I runs over compositions with parts in a prescribe...
EJC
2010
13 years 5 months ago
2010
The concept of permutograph is introduced and properties of integral functions on permutographs are established. The central result characterizes the class of integral functions t...
EJC
2010
13 years 5 months ago
2010
Most of these problems were presented at the conference on Combinatorics, Geometry and Computer Science, held at CIRM, Luminy, 2-4 May 2007. I have added one problem on a similar ...
EJC
2010
13 years 5 months ago
2010
EJC
2010
13 years 5 months ago
2010
EJC
2010
13 years 5 months ago
2010
EJC
2010
13 years 5 months ago
2010
EJC
2010
13 years 5 months ago
2010
Let a graph be locally disjoint union of three copies of complete graphs Kq-1 and let be cospectral with the Hamming graph H(3, q). Bang and Koolen [Asian-Eur. J. Math. 1 (2008),...
EJC
2010
13 years 5 months ago
2010
Packing density is a permutation occurrence statistic which describes the maximal number of permutations of a given type that can occur in another permutation. In this article we ...