A note on consecutive ones in a binary matrix.
A note on the number of derangements.
A note on the number of squares in a partial word with one hole
A well known result of Fraenkel and Simpson states that the number of distinct squares in a word of length n is bounded by 2n since at each position there are at most two distinct squares whose last occurrence starts. In this paper, we investigate squares in partial words with one hole, or sequences over a finite alphabet that have a “do not know” symbol or “hole”. A square in a partial word over a given alphabet has the form uv where u is compatible with v, and consequently, such square is...
A -analogue of a formula of Frobenius.
A permutation regularity lemma.
A permutations representation that knows what “Eulerian” means.
A recurrence relation for the “inv" analogue of -Eulerian polynomials.
A study of Eulerian numbers for permutations in the alternating group.
A theorem on chains of finite sets, II
A variant of the reciprocal super Catalan matrix
Recently Prodinger [8] considered the reciprocal super Catalan matrix and gave explicit formulæ for its LU-decomposition, the LU-decomposition of its inverse, and obtained some related matrices. For all results, q-analogues were also presented. In this paper, we define and study a variant of the reciprocal super Catalan matrix with two additional parameters. Explicit formulæ for its LU-decomposition, LUdecomposition of its inverse and the Cholesky decomposition are obtained. For all results, q-analogues...
Affine permutations and inversion multigraphs.
Affine permutations of type .
Alternating, pattern-avoiding permutations.
An answer to a question by Wilf on packing distinct patterns in a permutation.
An application of Halls' theorems to matrices
An application of Tao's analytic method to restricted sumsets
An Attempt at Frankl's Conjecture
An identity for the independence polynomials of trees.
An infinite antichain of permutations.
An interesting new Mahonian permutation statistic.