graph theory
Edwin Clark
eclark at math.usf.edu
Sat Jan 8 02:58:51 CET 2005
I think what you are dealing with has also been called the corona of a
graph. I think you will agree that if you "ciliate" (in your terms) a
cycle you will get something that looks like a crown (or corona).
Anyhow graph theorists have a somewhat more general concept
involving two graphs:
"The corona $G_1\circ G_2$ of two graphs $G_1$ and $G_2$ was defined by
Frucht and Harary as the graph $G$ obtained by taking one copy of $G_1$
which has $p_1$ vertices and $p_1$ copies of $G_2$ and then joining the
$i$th vertex of $G_1$ to every vertex in the $i$th copy of $G_2$.
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If you take G_2 to be the trivial one vertex graph you will get what some
call the corona of G1. I have seen this construction several place without
a name, but corona seems to have taken. If you search MathSciNet using
Anywhere: corona and Anywhere: graph, you get a large number of hits.
Although I'm not sure they all lead to the same concept.
--Edwin Clark
PS. As for improving on your wording if I understand you correctly you
need to mention the new edges as well as the new vertices.
PPS The above definition was taken from the MathSciNet abstract:
MR1980055 (2004e:05166)
Bhat-Nayak, Vasanti N.(6-BOMB); Telang, Shanta(6-BOMB)
Cahit-$k$-equitability of $C\sb n\circ K\sb 1$, $k=n$ to $2n-1$, $n\geq
3$.
Proceedings of the Thirty-third Southeastern International Conference on
Combinatorics, Graph Theory and Computing (Boca Raton, FL, 2002).
Congr. Numer. 155 (2002), 131--213.
On Fri, 7 Jan 2005, Emeric Deutsch wrote:
> Dear seqfans,
> In view of submitting new sequences to OEIS, I'd like to pick the
> brain of graph theorists.
>
> Let G be a graph with n vertices. By the ciliation of G we mean
> the graph obtained from G by joining n new vertices to the n
> vertices of G, respectively.
>
> For example, a path graph becomes a "comb".
>
> My first question: is "ciliation" a good term for this new graph?
> Any suggestions?
>
> My second question: can one improve on the wording of "the graph
> obtained from G by joining n new vertices to the n vertices of G,
> respectively" ?
>
> Many thanks and Happy 2005.
> Emeric
>
> P.S. The second graph (the ciliation of G) is an "equible" graph
> in the terminology of Farrell-Kennedy-Quintas-Wahid.
>
--
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W. Edwin Clark, Math Dept, University of South Florida
http://www.math.usf.edu/~eclark/
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