let N be non empty with_non-empty_elements set ; for S being non empty stored-program IC-Ins-separated steady-programmed definite standard AMI-Struct of N
for F being Subset of NAT holds card F c= order_type_of (RelIncl (LocNums F,S))
let S be non empty stored-program IC-Ins-separated steady-programmed definite standard AMI-Struct of N; for F being Subset of NAT holds card F c= order_type_of (RelIncl (LocNums F,S))
let F be Subset of NAT ; card F c= order_type_of (RelIncl (LocNums F,S))
set X = LocNums F,S;
F, LocNums F,S are_equipotent
by Th27;
then
( card (LocNums F,S) = card (order_type_of (RelIncl (LocNums F,S))) & card F = card (LocNums F,S) )
by CARD_1:21, CARD_5:16;
hence
card F c= order_type_of (RelIncl (LocNums F,S))
by CARD_1:24; verum