A lemma (entry) may depend on lemmas (entries) below its position, but never on lemmas above its position. This means the list is a topological order of the dependency graph. An entry 'all subs proved' means that all used lemmas are (transitively) proved.
| Name: | Status: | Subs proved? | Used: |
|---|---|---|---|
| pack1 | proved | all subs proved | pack-nil, pack-rec, |
| pack-append | proved | all subs proved | pack-rec, pack-nil, |
| pack-nil | axiom | ||
| pack-rec | axiom |