User blog comment:Superman37891/Tetration Ten/@comment-30754445-20170607212457/@comment-25601061-20170626235641

Recursion is important in making large numbers. Start with a function, then nest that function, then nest the nesting, then nest that nesting, and then nest over the number of nestings. If you go further, you can eventually make linear (1D) arrays out of the nestings, and make all sorts of structures from there.