Zobrazeno 1 - 10
of 137
pro vyhledávání: '"Yeong-Nan Yeh"'
Publikováno v:
Journal of Combinatorial Optimization. 44:2832-2852
In this paper, motivated by many practical applications, we address the 1-line minimum rectilinear Steiner tree (1L-MRStT) problem, which is a variation of the Euclidean minimum rectilinear Steiner tree problem. More specifically, given n points in t
Publikováno v:
Discrete Mathematics. 345:112980
Publikováno v:
Journal of Combinatorial Theory, Series A. 167:257-293
In this paper, we study γ-positivity of descent-type polynomials by introducing the change of context-free grammars method. We first present a unified grammatical proof of the γ-positivity of Eulerian polynomials, type B Eulerian polynomials, deran
Publikováno v:
European Journal of Combinatorics. 78:236-255
Let [ R n , k ] n , k ≥ 0 be an array of nonnegative numbers satisfying the recurrence relation R n , k = ( a 1 n + a 2 k + a 3 ) R n − 1 , k + ( b 1 n + b 2 k + b 3 ) R n − 1 , k − 1 + ( c 1 n + c 2 k + c 3 ) R n − 1 , k − 2 with R 0 , 0
Publikováno v:
Discrete Mathematics. 342:836-843
We view an undirected graph G as a symmetric digraph, where each edge x y is replaced by two opposite arcs e = ( x , y ) and e − 1 = ( y , x ) . Assume S is an inverse closed subset of permutations of positive integers. We say G is S - k -colourabl
Publikováno v:
Mathematical Proceedings of the Cambridge Philosophical Society. 168:505-518
Let χ(t) = a0tn – a1tn−1 + ⋯ + (−1)rartn−r be the chromatic polynomial of a graph, the characteristic polynomial of a matroid, or the characteristic polynomial of an arrangement of hyperplanes. For any integer k = 0, 1, …, r and real num
Publikováno v:
Discrete Mathematics. 345:112714
In this paper we present grammatical interpretations of the alternating Eulerian polynomials of types A and B. As applications, we derive several properties of the type B alternating Eulerian polynomials, including combinatorial expansions, recurrenc
In this paper, we give a type B analogue of the 1/k-Eulerian polynomials. Properties of this kind of polynomials, including combinatorial interpretations, recurrence relations and gamma-positivity are studied. In particular, we show that the 1/k-Eule
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8c1e808f48ed5c5e189f7d7f18932869
http://arxiv.org/abs/2001.07833
http://arxiv.org/abs/2001.07833
In this paper, we characterize a duality relation between Eulerian recurrences and Eulerian recurrence systems, which generalizes and unifies Hermite-Biehler decompositions of several enumerative polynomials, including flag descent polynomials for hy
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::79007319f752757c52047529e91d4ebe
Publikováno v:
Discrete Mathematics. 341:2478-2484
A permutation of the multiset { 1 , 1 , 2 , 2 , … , n , n } is called a Stirling permutation of order n if every entry between the two occurrences of i is greater than i for each i ∈ { 1 , 2 , … , n } . In this paper, we introduce the definitio