# How to use Notation package with TraditionalForm

I know that I can use the Notation package to define my own custom notation. This works great for StandardForm output, but I would like the notation to apply when I convert it to TraditionalForm. For example:

Notation[△ θ_ ⟸ △[θ_]]


This tells Mathematica that if it finds a laplacian operator, mathematica should display it without the brackets. This works fine in StandardForm. However, if I use TraditionalForm, then Mathematica inserts parentheses instead of following the rule.

How can I make the rule apply to TraditionalForm?

-

Format[△[θ_], TraditionalForm] := HoldForm[△ θ]
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