A Lookup Table is an unusual element in that it does not have any inputs that accept links from other elements (since the entries to the table must be numbers). As a result, when you view a Lookup Table in the graphics pane, you will note that it never has an input port.
In addition, the output of a Lookup Table itself is not an actual value; rather it is simply a definition that does not take on a value unless you add the appropriate arguments.
As a result, the browser view of a Lookup Table is unusual in that it does not show any inputs or outputs (even when you have chosen the option to display these in the browser by selecting Show Element Subitems):
Note: If the table is defined using an external function, the Table does
have an input port and a single input – the table definition.
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