Some Results on Berge’s Conjecture and Begin–End Conjecture

نویسندگان

چکیده

Let D be a digraph. A subset S of V(D) is stable if every pair vertices in non-adjacent D. collection disjoint paths $$\mathcal {P}$$ path partition V(D), vertex on . We say that set and are orthogonal contains exactly one S. digraph satisfies the $$\alpha $$ -property for maximum D, there to -diperfect induced subdigraph -property. In 1982, Berge proposed characterization digraphs terms forbidden anti-directed odd cycles. 2018, Sambinelli, Silva Lee similar conjecture. Begin–End-property or BE-property such (i) (ii) each $$P\in \mathcal , either initial final P lies BE-diperfect BE-property. blocking this paper, we show some structural results digraphs. particular, minimal counterexample both conjectures, it follows (D) < \vert V(D)\vert /2$$ Moreover, prove conjectures arc-locally (out) in-semicomplete

برای دانلود باید عضویت طلایی داشته باشید

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

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Some difference results on Hayman conjecture and uniqueness

In this paper, we show that for any finite order entire function $f(z)$, the function of the form $f(z)^{n}[f(z+c)-f(z)]^{s}$ has no nonzero finite Picard exceptional value for all nonnegative integers $n, s$ satisfying $ngeq 3$, which can be viewed as a different result on Hayman conjecture. We also obtain some uniqueness theorems for difference polynomials of entire functions sharing one comm...

متن کامل

On some generalisations of Brown's conjecture

Let $P$ be a complex polynomial of the form $P(z)=zdisplaystyleprod_{k=1}^{n-1}(z-z_{k})$,where $|z_k|ge 1,1le kle n-1$ then $ P^prime(z)ne 0$. If $|z|

متن کامل

some difference results on hayman conjecture and uniqueness

in this paper, we show that for any finite order entire function $f(z)$, the function of the form $f(z)^{n}[f(z+c)-f(z)]^{s}$ has no nonzero finite picard exceptional value for all nonnegative integers $n, s$ satisfying $ngeq 3$, which can be viewed as a different result on hayman conjecture. we also obtain some uniqueness theorems for difference polynomials of entire functions sharing one comm...

متن کامل

On Lee's conjecture and some results

S.M. Lee proposed the conjecture: for any n > 1 and any permutation f in S(n), the permutation graph P (Pn, f) is graceful. For any integer n > 1 and permutation f in S(n), we discuss the gracefulness of the permutation graph P (Pn, f) if f = ∏l−1 k=0(m + 2k, m + 2k + 1), and ∏l−1 k=0(m+4k, m+4k +2)(m+4k +1, m+4k +3) for any positive integers m and l.

متن کامل

Some New Results on Liu’s Conjecture

Consider the problem of scheduling n tasks with precedence constraint ≺ on m parallel processors so as to minimize the makespan. Let ω and ω′ be the makespans of the optimal nonpreemptive and optimal preemptive schedules, respectively. Liu’s conjecture states that ω ω′ ≤ 2m m+1 . In this paper, we present a simple proof of the conjecture for ≺= ∅, and give an improved bound closer to that in th...

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

ژورنال

عنوان ژورنال: Graphs and Combinatorics

سال: 2022

ISSN: ['1435-5914', '0911-0119']

DOI: https://doi.org/10.1007/s00373-022-02509-8