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Polynomial sequences generated by infinite Hessenberg matrices

Luis Verde-Star (2017)

Special Matrices

We show that an infinite lower Hessenberg matrix generates polynomial sequences that correspond to the rows of infinite lower triangular invertible matrices. Orthogonal polynomial sequences are obtained when the Hessenberg matrix is tridiagonal. We study properties of the polynomial sequences and their corresponding matrices which are related to recurrence relations, companion matrices, matrix similarity, construction algorithms, and generating functions. When the Hessenberg matrix is also Toeplitz...

Polynomials of multipartitional type and inverse relations

Miloud Mihoubi, Hacène Belbachir (2011)

Discussiones Mathematicae - General Algebra and Applications

Chou, Hsu and Shiue gave some applications of Faà di Bruno's formula to characterize inverse relations. Our aim is to develop some inverse relations connected to the multipartitional type polynomials involving to binomial type sequences.

Primal-dual approximation algorithms for a packing-covering pair of problems

Sofia Kovaleva, Frits C. R. Spieksma (2002)

RAIRO - Operations Research - Recherche Opérationnelle

We consider a special packing-covering pair of problems. The packing problem is a natural generalization of finding a (weighted) maximum independent set in an interval graph, the covering problem generalizes the problem of finding a (weighted) minimum clique cover in an interval graph. The problem pair involves weights and capacities; we consider the case of unit weights and the case of unit capacities. In each case we describe a simple algorithm that outputs a solution to the packing problem and...

Primal-dual approximation algorithms for a packing-covering pair of problems

Sofia Kovaleva, Frits C.R. Spieksma (2010)

RAIRO - Operations Research

We consider a special packing-covering pair of problems. The packing problem is a natural generalization of finding a (weighted) maximum independent set in an interval graph, the covering problem generalizes the problem of finding a (weighted) minimum clique cover in an interval graph. The problem pair involves weights and capacities; we consider the case of unit weights and the case of unit capacities. In each case we describe a simple algorithm that outputs a solution to the packing problem and...

Probability measures corresponding to Aval numbers

Wojciech Młotkowski (2012)

Colloquium Mathematicae

We describe the class of probability measures whose moments are given in terms of the Aval numbers. They are expressed as the multiplicative free convolution of measures corresponding to the ballot numbers ( m - k ) / ( m + k ) m + k m .

Probability that an element of a finite group has a square root

M. S. Lucido, M. R. Pournaki (2008)

Colloquium Mathematicae

Let G be a finite group of even order. We give some bounds for the probability p(G) that a randomly chosen element in G has a square root. In particular, we prove that p(G) ≤ 1 - ⌊√|G|⌋/|G|. Moreover, we show that if the Sylow 2-subgroup of G is not a proper normal elementary abelian subgroup of G, then p(G) ≤ 1 - 1/√|G|. Both of these bounds are best possible upper bounds for p(G), depending only on the order of G.

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