Báo cáo toán học: "New regular partial difference sets and strongly regular graphs with parameters (96,20,4,4) and (96,19,2,4)" ppsx
Báo cáo toán học: "Generalizations of Partial Difference Sets from Cyclotomy to Nonelementary Abelian p-Groups" pdf
... D and D
(−1)
= D we call the PDS D regular. Regular partial
difference sets are equivalent to strongly regular Cayley graphs [11] and [18]. Latin square
and negative Latin square type partial difference ... Hadamard difference sets and a new family
of difference sets. Finite Fields and their Applications, 3 (1997) 234-256.
[6] J. A. Davis and Q. Xiang, Negati...
Báo cáo toán học: "New infinite families of almost-planar crossing-critical graphs" ppsx
... such
crossing-critical graphs as almost-planar which was not the case of previous constructions.
Our construction works with all (not too small) values of k, and not only with sporadic
large k’s as, say [11], and ... simple graphs G
1
, G
2
with cubic vertices u
i
∈ V (G
i
) and their neighbors denoted by
r
i
, s
i
, t
i
, the zip product G of G
1
and G
2
, according to the...
Báo cáo toán học: "A note on the component structure in random intersection graphs with tunable clustering" pptx
... evolution in random intersection graphs. The Electronic
Journal of Combinatorics, 14, #R17, 2007.
[3] M. Deijfen and W. Kets. Random intersection graphs with tunable degree distribu-
tion and clustering. ... S. Janson, T. Luczak and A. Ruci´nski. Random Graphs. John Wiley & Sons, 2000.
[5] M. Karo´nski, E. R. Scheinerman, and K. B. Singer-Cohen. On random intersection
grap...
Báo cáo toán học: "New regular partial difference sets and strongly regular graphs with parameters (96,20,4,4) and (96,19,2,4)" ppsx
... Algorithms, and Programming, Version
4.3; Aachen, St. Andrews (1999).
the electronic journal of combinatorics 13 (2006), #R88 10
New regular partial difference sets and strongly regular
graphs with parameters ... partial difference sets S
1
and S
2
in a group H, the graphs Cay(H, S
1
) and Cay(H, S
2
) can be isomorphic. Similarly, for
two inequivalent partial...
Báo cáo toán học: "New symmetric designs from regular Hadamard matrices" pdf
... regular Hadamard matrix of order 4 and H is a regular
Hadamard matrix of order 9 · 4
d+1
. Therefore, one can obtain a family of regular
Hadamard matrices of order 9 · 4
d
, starting with a regular ... the
construction of the corresponding M and G given in [6]
3 (36, 15, 6)- and (36, 21, 12) -difference sets
We start with a brief description of the Spence (36, 15, 6) -diffe...
Báo cáo toán học: " New proofs of Schur-concavity for a class of symmetric functions" potx
... symmetric and has a nonempty interior convex
set. Ω
0
is the interior of Ω. ϕ : Ω → R is continuous on Ω and differentiable in
Ω
0
. Then ϕ is the Schur-convex (Schur-concave) function, if and only ... if
k
i=1
x
[i]
≤
k
i=1
y
[i]
for k = 1, 2, . . . , n − 1 and
n
i=1
x
i
=
n
i=1
y
i
, where x
[1]
≥ · · · ≥ x
[n]
and
y
[1]
≥ · · · ≥ y
[n]
are rearrangements of x and y in a...
Báo cáo toán học: "New Characterizations and Generalizations of PP Rings" ppt
... Therefore aR
⊕
R
R
, and hence a is regular.
(5) ⇒ (1) and (3). Since X is regular, aR is a summand of R
R
for any a ∈ X.
Hence (1) and (3) hold.
(3) ⇒ (4). Using [22, Lemma 1.1] and the proof of ... proven
that R is regular if and only if R is right J-PP and right weakly continuous if
and only if every right R-module has a PI-envelope with the unique mapping
property i...
Báo cáo toán học: " New Lower Bounds for Some Multicolored Ramsey Numbers" pot
... #R3 6
[GG] R. Greenwood and A. Gleason, Combinatorial Relations and Chromatic Graphs,
Canadian Journal of Mathematics, 7, 1955, 1-7.
[K]J.Kalbfleisch,Chromatic Graphs and Ramsey’s Theorem, (Ph.D. ... to search. We
then call the procedure diffcheck to choose all possible 3 -sets (for B, C,andD )and
check whether or not the differences between any two elements are all cubic residues....
Báo cáo toán học: "New Bounds for Codes Identifying Vertices in Graphs" pdf
... g5toincreasebyoneonly(ifwetakei4andi6ascodewords).
But then the covering of h2, f0andh0 requires an increase of the degree of g1ofat
least two, and in the best case we end up with degrees four, three and four for e5,g5
and ... vertices with degree
exactly three in Γ and B is the set of vertices with degree at most two in Γ. We
partition C
into two sets, X and Y : X contains...
Báo cáo toán học: "NEW UPPER BOUNDS ON THE ORDER OF CAGES1" pps
... Margulis [16] and, independently, Lubotzky, Phillips and Sarnak [15] came up
with similar examples of graphs with γ ≥ 4/3 and arbitrary large valency (they
turned out to be so–called Ramanujan graphs) . ... Bollob´as, Random Graphs, Academic Press, London, 1985.
6. A. E. Brouwer, A. M. Cohen, A. Neumaier, Distance -Regular Graphs, Springer-
Verlag, Heidelberg – New York, 1989....