Problem installing "clusplot" on Mac Mojave

How can I fix this?

install.packages("clusplot")
Warning in install.packages :
package ‘clusplot’ is not available for this version of R

A version of this package for your version of R might be available elsewhere,
see the ideas at

There is a clusplot() function in the cluster package, but I am unable to find a package named clusplot.
Try install.packages("cluster").