User blog comment:! cook the lettuce/Despacit's Number Competition/@comment-38877333-20191207182319/@comment-36984051-20191208145142

T_99999[[[[999]_4]_3]_2] defines here: https://googology.wikia.org/wiki/User_blog:SuperSpruce/The_T_Array_Function_Part_5:_Arbitrary_Comma_T_Function_(ACT)