User blog comment:Username5243/Username5243's Array Notation/@comment-27516045-20160731021129

The double-comma will work similar to multi-argument phi notation. The triple-comma work expand to double-commas. I think that the limit of nested-dimensional-comma arrays is f_BHO(n). Then we will put multicomma arrays inside the comma-array, and with this I think we could get as far as psi(W_w).

I'll need to think beyond that, though.