Then {Gn} is a convergent graph sequence with limit W.
Note on Initial Idea of Convergent Graph Sequence
This is a {“local”} idea of convergence since it checks to see if {sampled subgraphs converge "in distribution" up to the limiting object}. This is called {==left convergence since it deals with left homomorphism densities==} t(F,Gn) and t~(F,W).
(we count the occurrences of the motif within the graph/graphon)
^note-1
Note
This is not the only way to identify a (dense) convergent graph sequence. Another definition is based on the convergence of {==min-cuts or right homomorphisms==} t(Gn,F) and t~(W,F).
This is a {more “global”} notion of convergence that is used sometimes by graph theorists or in physics (micro-canonical ground state energy)
^note-2
Note
For dense graphs, left and right convergence are equivalent (for the metric we like) without proof.