N
ested_
M
ultisets_
O
rdinals
Multiset_More
Signed_Multiset
Nested_Multiset
Hereditary_Multiset
Signed_Hereditary_Multiset
Syntactic_Ordinal
Signed_Syntactic_Ordinal
Syntactic_Ordinal_Bridge
McCarthy_91
Hydra_Battle
Goodstein_Sequence
Unary_PCF