The Extended Universe Size Index (EUSI) is a number, which indicates the deepest nestation of verses within a specific verse.
It can be used to tell the size of a universe, without needing to say its size, due to most verses having beyond infinite sizes, or ordinals/cardinals that aren't named yet.
EUSIs aren't confined to just verses either, they can be applied to other containers, boxes, structures (artifical or not), etc.
We define a function
After this, we can create another extention, by borrowing some things from other functions, such as the veblen function, by asserting:
EUSI in number form
EUSIs can obviously be broken down into ordinals / cardinals after they've been fully decomposed. The article of these is here.