User blog comment:KthulhuHimself/Plexation, TaN, and such/@comment-2033667-20151014063209

The definition of TaN is missing a lot of things. You need to explain more clearly what an "entry" is. In ]n {1} 1[ one might interpret "n", "{1}", and "1" to be the entries since you don't specify how the bracket notation represents strings. Although I was able to figure things out from the example, you should clarify this.

As for semantics, we can just keep applying your rule indefinitely like so:


 * ]n {1} 1[ = ])n( {1} 0[ = ]))n(( {1} -1[ = ])))n((( {1} -2[ = ...

Also, what happens when the string only has one entry? There's no second-to-last entry in that case.