like infinity 1-2-2-1 or 2-1-1-2 ; or 1-2-2-1 2-1-1 2 2-1-1-2 1-2-2-1 ; or 2-1-1-2 1-2-2-1 1-2-2-1 2-1-1-2 1-2-2-1 2-1-1-2 2-1-1-2 1-2-2-1 1-2-2-1 2-1-1-2 2-1-1-2 1-2-2-1 2-1-1-2 1-2-2-1 1-2-2-1 2-1-1-2 ; and so forth .