Use this if you are using igraph from R
| centr_betw_tmax {igraph} | R Documentation | 
See centralize for a summary of graph centralization.
centr_betw_tmax(graph = NULL, nodes = 0, directed = TRUE)
graph | 
 The input graph. It can also be   | 
nodes | 
 The number of vertices. This is ignored if the graph is given.  | 
directed | 
 logical scalar, whether to use directed shortest paths for calculating betweenness.  | 
Real scalar, the theoretical maximum (unnormalized) graph betweenness centrality score for graphs with given order and other parameters.
Other centralization related: 
centr_betw(),
centr_clo_tmax(),
centr_clo(),
centr_degree_tmax(),
centr_degree(),
centr_eigen_tmax(),
centr_eigen(),
centralize()
# A BA graph is quite centralized
g <- sample_pa(1000, m = 4)
centr_betw(g, normalized = FALSE)$centralization %>%
 `/`(centr_betw_tmax(g))
centr_betw(g, normalized = TRUE)$centralization