The Mycielskian construction, denoted ?(G), takes a finite simple graph G to larger with of the same clique number but chromatic number. generalized ?t(G), odd girth. In this chapter we look at symmetry parameters ?(G) and ?t(G) in terms G. These include determining number, distinguishing cost distinguishing.

The packing chromatic number χρ(G) of a graphG is the smallest integer k such that the vertex set of G can be partitioned into sets Vi, i ∈ [k], where each Vi is an i-packing. In this paper, we investigate for a given triple (a, b, c) of positive integers whether there exists a graph G such that ω(G) = a, χ(G) = b, and χρ(G) = c. If so, we say that (a, b, c) is realizable. It is proved that b =...

Let G be a finite connected simple graph and μ(G) be the Mycielskian of G. We show that for connected graphs G and H, μ(G) is isomorphic to μ(H) if and only if G is isomorphic to H. Furthermore, we determine the energy of the Mycielskian of a connected regular graph G in terms of the energy E(G) of G, where the energy of G is the sum of the absolute values of the eigenvalues of G. The energy of...

For a (molecular) graph, the hyper Zagreb index is defined as HM(G) = ∑ uv∈E(G) (dG(u) + dG(v)) 2 and the hyper Zagreb coindex is defined asHM(G) = ∑ uv/ ∈E(G) (dG(u)+dG(v)) 2. In this paper, the hyper Zagreb indices and its coindices of edge corona product graph, double graph and Mycielskian graph are obtained.

The generalized Mycielskians (also known as cones over graphs) are the natural generalization of the Mycielski graphs (which were first introduced by Mycielski in 1955). Given a graph G and any integer m 0, one can transform G into a new graph m(G), the generalized Mycielskian of G. This paper investigates circular clique number, total domination number, open packing number, fractional open pac...

It is shown in this note that some matching-related properties of graphs, such as their factor-criticality, regularizability and the existence of perfect 2-matchings, are preserved when iterating Mycielski’s construction.

We investigate some topological properties of a normal functor H introduced earlier by Radul which is a certain functorial compactification of the HartmanMycielski construction HM . We show that H is open and find the condition when HX is an absolute retract homeomorphic to the Tychonov cube.

In the context of arbitrary Polish groups, we investigate the Galvin– Mycielski–Solovay characterization of strong measure zero sets as those sets for which a meager collection of right translates cannot cover the

Let G be any abelian group and {asGs}ks=1 be a finite system of cosets of subgroups G1, . . . , Gk. We show that if {asGs} k s=1 covers all the elements of G at least m times with the coset atGt irredundant then [G : Gt] 6 2 and furthermore k > m + f([G : Gt]), where f( ∏ r i=1 p αi i ) = ∑ r i=1 αi(pi − 1) if p1, . . . , pr are distinct primes and α1, . . . , αr are nonnegative integers. This ...