Definition:Addition/Multiindices

Definition
The addition operation in the domain of multiindices $Z$ is written $+$.

If $k = \left \langle {k_j}\right \rangle_{j \in J}$ and $\ell = \left \langle {\ell_j}\right \rangle_{j \in J}$ are multiindices.

Then $k + \ell$ is defined by:
 * $\left( \forall j \in J \right) \left( \left( k + \ell \right)_j = k_j + \ell_j \right)$