Báo cáo toán học: "On hypergraphs with every four points spanning at most two triples" ppsx

... 6), such that every four points span 0 or 2 edges, has at most 10(m/6) 3 edges (their result is quite a bit stronger, but this version suffices for our purposes). We will use this on subhypergraphs of ... proving that a positive proportion of quadruples contribute to q 1 . By (1) this immediately lowers the bound of 1/3. Our primary tool is a result of Frankl and F¨uredi [4] stating t...

Ngày tải lên: 07/08/2014, 07:21

... girth at least three, which states that an r-graph, without a pair of sets intersecting in at least two points, has at most  n 2  /  r 2  edges, and the equality is attained for each r ≥ 3 and ... probability that the number of cycles of length at most four in H is at least 1 4 r −4r/3 n 4/3 is less than 1 2 . Therefore, with positive probability, H has at least 1 2...

Ngày tải lên: 07/08/2014, 07:21

... graph Γ with defect 2, if there are at least 2 paths of length at most D(Γ) from a vertex v to a vertex u, then we say that v is a repeat of u (and vice ve rsa) . In this case we have two repeats ... we show that cos α must be an algebraic integer of degree at most 4. We then note that if, for a given d and an eigenvalue λ, Equation (9) has at least two values of k, then α m...

Ngày tải lên: 08/08/2014, 12:22

... such that U ⊂ F (f n ), ∀n  0. Since the Fatou set is totally invariant, we can replace x with a finite iteration f i (x) at any stage of the argument. For each x ∈ F (f ), under iterating f i (x) ... compatible with dynamics; see [4]. This means that for each c ∈ B σ (c 0 )themapj c : ω(0) → C is injective and for each z ∈ ω(0) the function c → j c (z) is holomorphic. Being compatible...

Ngày tải lên: 06/08/2014, 05:20

... the recurrence relations for the analyzed quantities translate to equations over generating functions in a natural way, almost automatically. THE ELECTRONIC JOURNAL OF COMBINATORICS 5 (1998), ... by [X]=  (X−µ) 2  =  X 2  + [X]− [X] 2 . Since we will mostly deal with families of random variables, with two (n and j)orone(n) index, we will systematically work with multivariate gener...

Ngày tải lên: 07/08/2014, 06:22

... shape 2 × k, filled with numbers from {1, ,n}. Consider the sum  ∆  ∈P k  Γ⊥∆  τ Γ . We claim that only τ Γ ’s for Γ of type at most n−k appear in this sum. We also claim that the coefficient of ... therefore we can assume that a Γ ≥ b Γ .ObservethatΓ 0 is the only horizontal tableau such that (a Γ 0 ,b Γ 0 )=(n, 0). Let T a be the collection of horizontal tableaux Γ with a Γ = a,and...

Ngày tải lên: 07/08/2014, 08:22

... (5) Assume indirectly that there is a (p, q)-coloring of K n with at most h colors. From this assumption we will get a contradiction. Consider a fixed (p, q)-coloring of K n with at most h colors. We ... linear and quadratic orders of magnitude, so for q lin ≤ q ≤ q quad . In particular we show that that we can have at most log p values of q which give a linear f(n, p, q). In o...

Ngày tải lên: 07/08/2014, 07:21

... generalized weakly directional contractions and approximate fixed point property with applications Wei-Shih Du Department of Mathematics, National Kaohsiung Normal University, Kaohsiung 824, Taiwan Email ... approximate fixed point property [7] in K provided inf x∈K d(x, T x) = 0. Clearly, F(T) = ∅ implies that T has the approximate fixed point property. A natural generalization of the approx...

Ngày tải lên: 20/06/2014, 20:20

Ngày tải lên: 05/08/2014, 09:46

Ngày tải lên: 05/08/2014, 10:20