What do you call order 3 tensor-like something but doesn't have to be independent on coordinate transformation?

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What is the term used to refer multi-dimensional array of programming languages in mathematics?

I thought it was tensor, but I learned that tensors should obey some restrictions(indepentent on coordinate transform, ...)

For example:

A order 0 tensor is a scalar.

A order 1 tensor is a vector.

A order 2 tensor is a matrix.

What do you call order 3 tensor-like something but doesn't have to be independent on coordinate transformation?

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My guess is that you are misunderstanding what it means to be independent under coordinate transformations and you can call your object a rank 3 tensor, or better yet, an element of $\mathbb{R}^{n_1\times n_2 \times n_3}$.

For example, invariance under coordinate transformations does not mean that your array has to be symmetric in any way.

Invariance under coordinate transformations only makes sense in a physical context and if your array of numbers actually comes from such a context then chances are that your array is invariant without you knowing it. Without going into details, any list or array of numbers can represent a tensor (-field, to be precise) but that depends on where they come from in your context and I don't think this discussion has anything to do with what you want to do.