User blog comment:Edwin Shade/Defining LOCC (Language Of Ordinal Construction)/@comment-25337554-20170927044815/@comment-32876686-20170927194843

If m[n] means the nth element of m then yes; and yes, it is allowed to write " (n)eoT(a,b)=T((n)eo(a),b)" so that ordinal arguments bigger than omega can be defined.