User blog comment:Mh314159/Question about growth rate/@comment-35470197-20191107005001/@comment-35470197-20191107122813

There is no direct way to extend f_{ω^2} to f_{ω^3}. As I explained in a comment to your blog post, you need to diagonalise f_{ω^2×n} (n=0,1,2,…).