Báo cáo toán hoc:" Subsequence Sums of Zero-sum-free Sequences Pingzhi Yuan " doc

... contradiction. ✷ the electronic journal of combinatorics 16 (2009), #R97 11 Subsequence Sums of Zero-sum-free Sequences Pingzhi Yuan School of Mathematics, South China Normal University, Guangzhou 510631, ... zero-sumfree sequences of r elements in G. In 19 72, Eggleton and Erd˝os (see [4]) first t ackled the problem of determining the minimal cardinality of  (S) for...

Ngày tải lên: 08/08/2014, 01:20

... simple proof of a nice formula for the means and covari- ances of the diagonal sums of a uniformly random boxed plane parition. An a × b × c boxed plane partition is an a × b grid of integers ... combinatorics 8 (2001), #N1 3 Diagonal Sums of Boxed Plane Partitions David B. Wilson Microsoft Research One Microsoft Way Redmond, WA 98052 dbwilson@microsoft.com Submitted: December 8...

Ngày tải lên: 07/08/2014, 06:22

... version of Graffiti made number of conjectures about operations R and B (derived from the chromatic number) and we included a sample of them in the first draft of this paper. Since then, most of these ... proved it in some cases and established all lower bounds. Examples of critical P (r, b) graphs are disjoint unions of b − 1 copies of of complete k-partite graphs in which every...

Ngày tải lên: 07/08/2014, 06:20

... The set of partial latin squares of order n is denoted by PLS(n), and the set of latin squares of order n by LS(n). We say that P 1 ∈ PLS(n) contains P 2 ∈ PLS(n) if every filled cell of P 2 agrees ... Cayley table of G is invariant with the enumeration chosen for G, so to complete the proof of the theorem it suffices to exhibit a 2-partition of L. We do this by first arguing that...

Ngày tải lên: 07/08/2014, 06:23

... colouring of U can be extended to a U-proper (L, 2) ∗ -colouring of G 1 , and that the resulting colouring of X can be extended to an X-pro per (L, 2) ∗ -colouring of G 2 , and the union of these ... G such that one endvertex of P is an internal vertex of P ab , the other endvertex is a vertex of H ′ that is not in P ab , and no other vertex of P i s in H ′ . Proof. If there...

Ngày tải lên: 08/08/2014, 01:20

... efficients of F are negligible compared to those of A because of Comment 2 above. We will use these ideas without explicit mention when considering error bounds. 4 Proof of Theorem 1 The value of A g (r) ... pieces) and the genus of G is the sum of the genera of all blocks [2]. We divide all connected graphs of genus g > 0 into two classes according to whether there is a bl...

Ngày tải lên: 08/08/2014, 12:23

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Ngày tải lên: 05/08/2014, 15:21

... journal of combinatorics 12 (2005), #R29 17 Asymptotic Enumeration of Dense 0-1 Matrices with Equal Row Sums and Equal Column Sums E. Rodney Canfield ∗ Department of Computer Science University of ... enumeration of 0-1 matrices with equal row sums and equal column sums, Linear Alg. Appl., 373 (2003) 273–288. [15] B. D. McKay and N. C. Wormald, Asymptotic enumeration by degree...

Ngày tải lên: 07/08/2014, 13:21

... of the FWHM of L1 emission lines for a series of Mn concentrations. Figure 4. The emission intensity of the neutral acceptor-bound exciton line L1. The emission intensity is a function of ... around the vacancy site, thus softening the normal-mode frequencies of the lattice and reducing the zero-point energy of the oscillators. An increase in the number of Mn atoms in t...

Ngày tải lên: 20/06/2014, 20:20

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Ngày tải lên: 20/06/2014, 20:20