Multigrade operator

In logic and mathematics, a multigrade operator \(\Omega\) is a parametric operator with parameter k in the set N of non-negative integers.

The application of a multigrade operator \(\Omega\) to a finite sequence of operands (x₁, …, x_k) is typically denoted with the parameter k left tacit, as the appropriate application is implicit in the number of operands listed. Thus \(\Omega\)(x₁, …, x_k) may be taken for \(\Omega\)_k(x₁, …, x_k).