Báo cáo toán học: "The approximative point spectrum of a subnormal operator " docx

... defined the fixed point index of 1-set- contractive operators and obtained some fixed point theorems of 1-set-contractive opera- tors. Recently, Li [6] obtained some fixed point theorems for 1-set-contractive ... Wang: The fixed point theorems of 1-set-contractive operators in Banach space. Fixed Point Theory and Applications 2011 2011:15. Wan...

Ngày tải lên: 21/06/2014, 02:20

... class="bi x0 y1 w1 h 2" alt =""

Ngày tải lên: 05/08/2014, 10:20

... class="bi x0 y0 w2 h 1" alt =""

Ngày tải lên: 05/08/2014, 15:20

... 1–8. 4. W. Li, On the property of solutions of M-matrix equations, Systems Science and Math. S cience 10 (1997) 129–132. The Bounds on Comp onents of the Solution for Consistent Linear Systems ... a nonsingular M-matrix. Hence the result follows immediately from Theorem 3.1 of [3]. Vietnam Journal of Mathematics 33:1 (2005) 91–95 The Bounds on Componen...

Ngày tải lên: 06/08/2014, 05:20

... polyominoes. The area |c| of the polyomino c is the number of its unit squares. We denote by C n the set of all the polyominoes of area n. The perimeter P (c) of a polyomino c is the number of ... c 1 and c 2 . Putting these facts together, we see that for the values of n listed in the theorem, the sets of the minimal antecedents through the sequen...

Ngày tải lên: 07/08/2014, 06:20

... point is a vertex. Such a drawing is said to be a rectilinear drawing of G.Therectilinear crossing number of G,denoted ν(G), is the fewest number of edge crossings attainable over all rectilinear ... rectilinear drawing of K n is a triangle. Prove that the convex hull of any optimal rectilinear drawing of K n is a triangle. 2. Given a rectilinear drawing...

Ngày tải lên: 07/08/2014, 06:22

... z}∈H}. the electronic journal of combinatorics 10 (2003), #R18 2 The Turan Density of the Hypergraph {abc, ade, bde, cde} Zoltan Făuredi Department of Mathematics, University of Illinois Urbana, ... both F 3,2 and F 2,3 and they are different. The extremal graph problem of F 3,2 originates from a Ramsey-Tur´an hypergraph paper of Erd˝os and T. S´os [2]. Th...

Ngày tải lên: 07/08/2014, 07:21

... eigenvalues, and showed that the eigenvalues that are neither dominant nor equal to 1 are o((log n) 2/5 ). Added in proof: our evaluation of the permanent of the original matrix of Redheffer, given in Theorem ... theoretic way, recall that an ordered factorization of an integer m is a representation m = a 1 a 2 a k ,inwhichalla i sare≥ 2 and the order of the f...

Ngày tải lên: 07/08/2014, 08:22

... that admits no cover pebbling, all pebbles may be concentrated to one of the fat nodes 1 with cover pebbling still not possible. Proof. Start with a distribution that admits no cover pebbling. If ... cover pebbling from f exceeds the total value of the pebbles. Therefore, cover pebbling is not possible with all pebbles initially on f .  4 The cover number for some classe...

Ngày tải lên: 07/08/2014, 08:22

... 7(1), (2000). [12] E. Spence, Strongly Regular Graphs,URL:http://www.maths.gla.ac.uk/~es/ srgraphs.html, (2004). the electronic journal of combina torics 13 (2006), #R32 9 (v, k, ,à) =(45, 12, 3, 3), providing ... at least n − 25. the electronic journal of combina torics 13 (2006), #R32 3 The Strongly Regular (45, 12, 3, 3) Graphs Kris Coolsaet, Jan Degraer Departm...

Ngày tải lên: 07/08/2014, 13:21

... permutation of X. In this paper, we show that if G is nilpotent of class c or supersolvable of length c then G always acts with distinguishing number at most c + 1. We obtain that all metacyclic ... groups act with distinguishing number at most 3; these include all groups of squarefree order. We also prove that the distinguishing number of the action of the general lin...

Ngày tải lên: 07/08/2014, 13:21

... B T C , where A is of size m ì m, B is of size m ì (n m) and C is of size (n m) ì (n m). The sizes of blocks are shown on the margins of the matrix. Let s denote the number of 1’s in B. Then ... elements of π are the last 3 elements of σ, i.e. 5 4 2. The middle part of π is the electronic journal of combinatorics 14 (2007), #R2 8 9 8 7. The first part of π is the permut...

Ngày tải lên: 07/08/2014, 15:22

... journal of combinatorics 15 (2008), #R4 11 The Minor Crossing Number of Graphs with an Excluded Minor Drago Bokal Department of Combinatorics and Optimization University of Waterloo Waterloo, Canada dbokal@uwaterloo.ca Gaˇsper ... Pinontoan and R. Bruce Richter. Crossing numbers of sequences of graphs. II. Planar tiles. J. Graph Theory, 42(4):332–341, 2003. [33...

Ngày tải lên: 07/08/2014, 15:22

... electronic journal of combinatorics 15 (2008), #R88 15 The 11-element case of Frankl’s conjecture Ivica Boˇsnjak and Petar Markovi´c ∗ Department of Mathematics and Informatics University of Novi Sad, ... p 2 (C x ) + 1 ≤ s(C x ). Note that the top set of C x is a level 5 set of C which contains {d, e, f, g}, while in the proof of q 2 ≤ p 5 in the previous case we used...

Ngày tải lên: 07/08/2014, 21:20

... dense random graph. The notion of a t-stable set is a generalisation of the notion of a stable set. Recall that a set of vertices S of a graph G is stable if no two of its vertices are adjacent. ... graphs. Combinatorica, 11(1):45–54, 1991. [19] D. Matula and L. Kuˇcera. An expose-and-merge algorithm and the chromatic number of a random graph. In Random Graph...

Ngày tải lên: 08/08/2014, 12:22