let n, m be Nat; for Y being ref-finite ConstructorDB
for B being FinSequence of the Constrs of Y st n <= m holds
ATMOST+ (B,n) c= ATMOST+ (B,m)
let Y be ref-finite ConstructorDB ; for B being FinSequence of the Constrs of Y st n <= m holds
ATMOST+ (B,n) c= ATMOST+ (B,m)
let B be FinSequence of the Constrs of Y; ( n <= m implies ATMOST+ (B,n) c= ATMOST+ (B,m) )
assume A1:
n <= m
; ATMOST+ (B,n) c= ATMOST+ (B,m)
let z be object ; TARSKI:def 3 ( not z in ATMOST+ (B,n) or z in ATMOST+ (B,m) )
assume A2:
z in ATMOST+ (B,n)
; z in ATMOST+ (B,m)
then
z in { y where y is Element of Y : card ((y ref) \ (rng B)) <= n }
by Def35;
then consider y being Element of Y such that
A3:
( z = y & card ((y ref) \ (rng B)) <= n )
;
card ((y ref) \ (rng B)) <= m
by A1, A3, XXREAL_0:2;
then
y in { x1 where x1 is Element of Y : card ((x1 ref) \ (rng B)) <= m }
;
hence
z in ATMOST+ (B,m)
by A2, A3, Def35; verum