Báo cáo toán học: "A quantitative ergodic theory proof of Szemer´di’s e theorem" pot

... alt =""

Ngày tải lên: 05/08/2014, 15:20

... class="bi x0 y1 w2 h 2" alt =""

Ngày tải lên: 05/08/2014, 15:21

... is (k, )-sum-free for k,  ∈ N, k>,ifthere are no solutions to the equation x 1 + ···+ x k = y 1 + ···+ y  in A. Denote by SF n k, the number of (k, )-sum-free subsets of [1,n]. Since the ... ρ). The main result of this note says that if (k − )/ is small in terms of ρ, then the number of (k, )-sum-free subsets of [1,n]isequalto(ϕ(ρ)+ϕ r...

Ngày tải lên: 07/08/2014, 06:20

... A note on the ranks of set-inclusion matrices D. de Caen Department of Mathematics and Statistics Queen’s University Kingston, Ontario, Canada K7L 3N6 decaen@mast.queensu.ca Submitted: ... relation is derived for the rank (over most fields) of the set-inclusion matrices on a finite ground set. Given a finite set X of say v elements, let W = W t,k (v) be the (0,1)-matr...

Ngày tải lên: 07/08/2014, 06:22

... E}. Since no directed C 4 contains v ∗ as a vertex, we must have that every w ∈ A appears in at least one of A − or A + (it may appear in both; in particular, v ∗ appears in both A − and A + as there ... A note on the number of edges guaranteeing a C 4 in Eulerian bipartite digraphs Jian Shen Department of Mathematics Southwest Texas State Unive...

Ngày tải lên: 07/08/2014, 06:23

... See http://mathworld.wolfram.com/BernsteinPolynomial.html the electronic journal of combinatorics 10 (2003), #R15 17 A Discontinuity in the Distribution of Fixed Point Sums Edward A. Bender Department of Mathematics University of ... n} whose fixed points sum to r, shows a sharp discontinuity in the neigh- borhood of r = n. We explain this discontinuity and stu...

Ngày tải lên: 07/08/2014, 07:21

... particular, it contains exactly one occurrence of the greatest letter it contains, since between two the electronic journal of combinatorics 11 (2004), #R17 3 Improved bounds on the length of maximal abelian square-free ... m. Further, if there is a pair of (k − 1)’s in w m , one must be on the left half of s m and hence before the m in h m+1 ,and the othe...

Ngày tải lên: 07/08/2014, 08:20

... B. E. Sagan, R. P. Stanley (Eds.), Mathematical Essays in honor of Gian-Carlo Rota, Birkauser, Basel. 1998, pp. 111-129 [3] Z. G. Liu, Some operator identities and q-series transformation formulas, ... (13) The proof is completed. References [1] G.E.Andrews,Ramanujan’s ”lost” notebook. I. Partial θ-functions, Adv. in Math. 41 (1981), 137-172 . [2] W.Y.C.Chen-Z.G.Liu,Parameter augmentation f...

Ngày tải lên: 07/08/2014, 08:22

... x j x i + x j Hf(B k,2n ). the electronic journal of combinatorics 12 (2005), #N9 5 A Pfaffian–Hafnian Analogue of Borchardt’s Identity Masao ISHIKAWA Faculty of Education, Tottori University Koyama, Tottori, ... there appeared a bijective proof of Borchardt’s identity (see [13]). It will be an interesting problem to give a bijective proof of (7) and (8). the electronic journ...

Ngày tải lên: 07/08/2014, 08:22

... electronic journal of combinatorics 12 (2005), #R4 17 A two-dimensional pictorial presentation of Berele’s insertion algorithm for symplectic tableaux Tom Roby Department of Mathematics California State ... serve as the inverse of the column insertion instead of the row insertion. It is also a semistandard version of a bijective tool used by Sundaram [Sun1, Pr...

Ngày tải lên: 07/08/2014, 08:22

... Classifications: 05E99, 16S34 Abstract In the context of generating functions for P -partitions, we revisit three flavors of quasisymmetric functions: Gessel’s quasisymmetric functions, Chow’s type B quasisymmetric ... on the set of all compositions of n by reverse refinement. The covering relations are of the form (α 1 , ,α i + α i+1 , ,α k ) ≺ (α 1 , ,α i ,α i+1 , ,α k ). L...

Ngày tải lên: 07/08/2014, 13:21

... repeat the above argument with the portion of R  beginning at u m−1 and the vertex u m . Theorem 1. Let h p (n) be the minimum number of distinct hamiltonian paths in a strong tournament of order ... are both transitive. the electronic journal of combinatorics 13 (2006), #N3 2 A Note on the Number of Hamiltonian Paths in Strong Tournaments Arthu...

Ngày tải lên: 07/08/2014, 13:21

... λ −z (X) . (8) the electronic journal of combinatorics 13 (2006), #R2 4 A Combinatorial Approach to Evaluation of Reliability of the Receiver Output for BPSK Modulation with Spatial Diversity S. ... u  is the word obtained by reading the positions of 1’s in M  — the right-hand part of M —, and w(r) is the the restriction of the tableau wo...

Ngày tải lên: 07/08/2014, 13:21

... der Waerden’s theorem directly. Also, as remarked above, the argument as presented here seems more able to extend to other recurrence problems. Remark 1.5. Our proof of Szemer´edi’s theorem here ... closely related to those used to prove van der Waerden’s theorem. The relevance of van der Waerden’s theorem and its generalizations in the ergodic theory approach is made more explicit...

Ngày tải lên: 07/08/2014, 13:21

... factorial. Corollary 3. The clas s of circular interval graphs and the class of l inear interval grap hs are fa ctorial. Proof. Corollary follows from the fact that both classes are subclasses of the class of circular ... that this class is a proper subclass of the class of circular arc graphs. A graph G is a circular arc graph if it is the intersection grap...

Ngày tải lên: 08/08/2014, 14:23