On separating sets of words. II.
On separating sets of words. IV.
On separating sets of words. V.
On some analogues of descent numbers and major index for the hyperoctahedral group.
On sums of distinct representatives
On symmetric and antisymmetric balanced binary sequences.
On symmetries and parallelogram spaces.
The notion of a TST-space is introduced and its connection with a parallelogram space is given. The existence of a TST-space is equivalent to the existence of a parallelogram space, which is a new characterization of a parallelogram space. The structure of a TST-space is described in terms of an abelian group.
On the combinatorics of permutations. (Zur Kombinatorik von Permutationen.)
On the diagram of Schröder permutations.
On the discrepancy of coloring finite sets.
On the excedance number of colored permutation groups.
On the - and -triangle of the barycentric subdivision of a simplicial complex
For a simplicial complex we study the behavior of its - and -triangle under the action of barycentric subdivision. In particular we describe the - and -triangle of its barycentric subdivision . The same has been done for - and -vector of by F. Brenti, V. Welker (2008). As a consequence we show that if the entries of the -triangle of are nonnegative, then the entries of the -triangle of are also nonnegative. We conclude with a few properties of the -triangle of .
On the measurement of the (non)linearity of Costas permutations.
On the number of antichains of finite power sets
On the number of permutations arising from a problem in cell-biology.
On the permutations generated by cyclic shift.
On the permutations generated by Sturmian words.
On the semigroup of binary relations on a finite set
On the Stanley-Wilf conjecture for the number of permutations avoiding a given pattern.
On the subspace of .