A generalization of Ramsey theory for linear forests

نویسندگان

  • A. Khamseh
  • Gholam Reza Omidi
چکیده

Chung and Liu defined the d-chromatic Ramsey numbers as a generalization of Ramsey numbers by replacing a weaker condition. Let 1 < d < c and let t = (c d ) . Assume A1, A2, . . . , At are all d-subsets of a set containing c distinct colors. Let G1, G2, . . . , Gt be graphs. The d-chromatic Ramsey number denoted by rc d(G1, G2, . . . , Gt) is defined as the least number p such that, if the edges of the complete graph Kp are colored in any fashion with c colors, then for some i, the subgraph whose edges are colored by colors in Ai contains a Gi. In this paper, we determine rc d(G1, G2, . . . , Gt) where Gi is a linear forest (disjoint union of paths) and d = c− 1 ≤ 3.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

On Generalization of Sturm-Liouville Theory for Fractional Bessel Operator

In this paper, we give the spectral theory for eigenvalues and eigenfunctions of a boundary value problem consisting of the linear fractional Bessel operator. Moreover, we show that this operator is self-adjoint, the eigenvalues of the problem are real, and the corresponding eigenfunctions are orthogonal. In this paper, we give the spectral theory for eigenvalues and eigenfunctions...

متن کامل

Local Ramsey numbers for linear forests

Let L be a disjoint union of nontrivial paths. Such a graph we call a linear forest. We study the relation between the 2-local Ramsey number R2-loc(L) and the Ramsey number R(L), where L is a linear forest. L will be called an (n, j)-linear forest if L has n vertices and j maximal paths having an odd number of vertices. If L is an (n, j)-linear forest, then R2-loc(L) = (3n − j)/2 + dj/2e −

متن کامل

Factorisation forests for infinite words Application to countable scattered linear orderings

The theorem of factorisation forests shows the existence of nested factorisations — a la Ramsey — for finite words. This theorem has important applications in semigroup theory, and beyond. We provide two improvements to the standard result. First we improve on all previously known bounds for the standard theorem. Second, we extend it to every ‘complete linear ordering’. We use this variant in a...

متن کامل

Factorization forests for infinite words and applications to countable scattered linear orderings

The theorem of factorization forests of Imre Simon shows the existence of nested factorizations — à la Ramsey — for finite words. This theorem has important applications in semigroup theory, and beyond. We provide two improvements to the standard result. First we improve on all previously known bounds. Second, we extend it to ‘every linear ordering’. We use this last variant in a simplified pro...

متن کامل

A Multivariate “inv” Hook Formula for Forests

Björner and Wachs provided two q-generalizations of Knuth’s hook formula counting linear extensions of forests: one involving the major index statistic, and one involving the inversion number statistic. We prove a multivariate generalization of their inversion number result, motivated by specializations related to the modular invariant theory of finite general linear groups.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Int. J. Comput. Math.

دوره 89  شماره 

صفحات  -

تاریخ انتشار 2012