Báo cáo toán học: "On domination in 2-connected cubic graphs" pps

... every cubic graph G containing F i and any dominating set D in G, the set D has at least 9 vertices in V (F i ). If D contains neither x i nor y i , then by Claim 1 D must contain 3 vertices in ... γ(H 2 −v 9 −v 10 ) = 6. In particular, every dominating set in any cubic graph containing V (H 2 ) has at least 6 vertices in V (H 2 ) − v 10 . The above claim is easy to check usin...

Ngày tải lên: 07/08/2014, 15:22

... strings corresponding to some standard Young tableau of shape λ beginning with some string w of length i − 1 followed by a, b and c in some order and ending by some v. We may neglect the strings ... tableau also corresponds to a string of numbers formed by reading the numbering in the order determined by the tableau. (This has been called the inverse reading word of the tableau.) A standa...

Ngày tải lên: 07/08/2014, 06:22

... questions, the most “interesting” subgraphs are the cycles. For this reason we consider only cycles in this paper. The girth of the graph is an interesting property which can be determined if enough ... other cycles whose length is in C. In fact, the resulting graph G 0 must be in R(m 1 , ,m t ). Let B denote the average number of ways to apply a backward r-switching to G 1 if G 1 is...

Ngày tải lên: 07/08/2014, 08:20

... Component evolution in random intersection graphs Michael Behrisch ∗ Institut f¨ur Informatik, Humboldt-Universit¨at zu Berlin, 10099 Berlin, Germany behrisch@informatik.hu-berlin.de Submitted: ... exp(c(ρ − 1)) (5) in the interval (0, 1). Thus the main complication in the proof is to overcome the limitations of the branching process which deals with an essentially unbounded domain in...

Ngày tải lên: 07/08/2014, 15:22

Ngày tải lên: 05/08/2014, 15:21

... positive integer l ≤ cn. It would be interesting to determine here the best possible value of the constant c. Perhaps it is c = 1 6 . One may obtain this trivial upper bound for 6|n by taking all ... following lemma: Lemma 1. The number of integers 1 ≤ k ≤ n satisfying φ(k) k < 1 t is less than n exp(− exp c 4 t) (where exp z = e z ), uniformly in t>2. This lemma can be found in [5]...

Ngày tải lên: 07/08/2014, 06:22

Ngày tải lên: 05/08/2014, 10:20

Ngày tải lên: 05/08/2014, 15:20

Ngày tải lên: 05/08/2014, 15:20

... algorithm, absolute performance ratio, almost sure perfor- mance ratio. 1. Introdu ction, Terminology, Main Result In certain problems called optimization problems we seek to find the optimal solution ... our guarantees, in terms of ratios, which was useful for comparison purpose and which seems to express nearness to optimality in a reasonable way. The terminology follows that in [1]....

Ngày tải lên: 06/08/2014, 05:20