as:A List, n:
(||as||-1). tl(as)[n] = as[(n+1)]a:T, as:T List, i:
. 0<i 
i
||as|| (a.as)[i] = as[(i-1)]| Theorem | Name |
| as:A List, n:(||as||-1). tl(as)[n] = as[(n+1)] | [select_tl] |
| cites the following: | |
| a:T, as:T List, i:. 0<i i||as|| (a.as)[i] = as[(i-1)] | [select_cons_tl] |