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Given a connected graph $G$ with $n$ vertices and given set of $\{m_1,m_2,...,m_n\}$ $n$ integers, we form a new graph $G{'}$ by considering the complete graph $K_{m_i}$ for each vertex i and 'join' (in the sense of graph theory) two of such complete graphs if the corresponding vertices are adjacent. Is there a name for this graph $G{'}$ associated to the Graph $G$?

By joining of two graphs $G_1$ and $G_2$, I mean introducing edges from all the vertices of $G_1$ to all the vertices of $G_2$ and vice versa, keeping the original edges as is.

Thanks for your valuable time.

Thanks a lot

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    $\begingroup$ Does this answer your question? Is there a name for Chain of complete bipartite graphs? $\endgroup$ Dec 29, 2021 at 20:17
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    $\begingroup$ I think the link to the later Question is helpful, but I don't feel especially satisfied by either the results of this Question or the other one. The older Answer (here) is actually a bit more convincing, so I'm going to put a bounty on it for a definitive Answer. $\endgroup$
    – hardmath
    Dec 30, 2021 at 19:58
  • $\begingroup$ As I noted in my Answer below, the proposed duplicate has an independent set $V_k$ in place of a vertex, so more or less the opposite of a clique $K_m$ described in this Question. So I don't see how these can be duplicates. However since I did post an Answer, I will skip the Close Review voting now. $\endgroup$
    – hardmath
    Jan 14, 2022 at 4:04

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I am not exactly sure of how your construction works, but I would start looking here. The lexicographic product might be what you are looking for. Hope this helps.

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  • $\begingroup$ sorry, I cant see how replacement product is related my notion. can you please explain your idea little bit. $\endgroup$
    – GA316
    Feb 12, 2016 at 3:56
  • $\begingroup$ I think that your construction is called the lexicographic product of graphs, where in your case $G^ := G \cdot K_m$. $\endgroup$ Feb 12, 2016 at 4:01
  • $\begingroup$ "By joining of two graphs G1G1 and G2G2, I mean introducing edges between all the vertices of G1G1 to all the vertices of G2G2 and viz. and keeping the original edges as it is." This is exactly the definition of the lexicographic product (also called graph composition). $\endgroup$ Feb 12, 2016 at 5:27
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My approach to finding "terminology" for this construction, replacing the $n$ vertices of given graph $G$ with cliques of varying sizes, was to search the literature for examples (and report what authors have chosen for terminology).

The varied sizes of cliques highlighted in this Question seemed particularly unmotivated. A paper which uses a fixed clique size in replacing all vertices is Clique-inserted-graphs and spectral dynamics of clique-inserting by Zhang, Chen and Chen (2009). But their term "clique-inserted graphs" could well be applied to the more general construction (allowing different clique sizes for each vertex $v\in G$).

A proof requiring just such variable sized cliques is described in the Wikipedia article on the perfect graph theorem of László Lovász (1972), settling a conjecture by Claude Berge (1961,1963):

Given a perfect graph $G$, Lovász forms a graph $G*$ by replacing each vertex $v$ by a clique of $t_v$ vertices, where $t_v$ is the number of distinct maximum independent sets in G that contain $v$.

A footnote to the Wikipedia article says, "We follow here the exposition of the proof by Reed (2001)." The terminology used by Reed (cf. Chapter 2, From Conjecture to Theorem) concerning the replacement of a vertex by a clique is easier to segregate than in Lovász:

Definition 2.16 We replicate a vertex $x$ in a graph $G$ by adding a vertex $x'$ adjacent to $x + N(x)$.

As Reed observes, "We can perform [substituting a clique for a vertex] by a series of replications."

Finally let me point out that in the recently proposed duplicate target, Is there a name for Chain of complete bipartite graphs?, the setup calls for parts $V_k$ of the graph which are independent sets, so it is inconsistent with the notion of parts that are cliques.

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