PlanetPhysics/Multigrade Operator

A multigrade operator $\Omega$ is a parametric operator with parameter $k$ in the set $\mathbb {N}$ of non-negative integers.

The application of a multigrade operator $\Omega$ to a finite sequence of operands $(x_{1},\ldots ,x_{k})$ is typically denoted with the parameter $k$ left tacit, as the appropriate application is implicit in the number of operands listed. Thus $\Omega (x_{1},\ldots ,x_{k})$ may be taken for $\Omega _{k}(x_{1},\ldots ,x_{k}).$