How to do core genome accumulation curve using Vegan

Question

[Heraud]

Hi, I am doing a bacterial pangenomic analysis comparing different strains.

I used Vegan package in R to plot the pangenome accumulation curve:

library(vegan)
specaccum(bin-matrix,"random",permutations=100)

But, I dont know how to do the core genome accumulation curve.

I will be grateful if anyone offer some advice to solve this problem.

Thanks for your help!