let R be /\-complete Semilattice; for N being net of R
for V being lower Subset of R st N is_eventually_in V holds
inf_net N is_eventually_in V
let N be net of R; for V being lower Subset of R st N is_eventually_in V holds
inf_net N is_eventually_in V
let V be lower Subset of R; ( N is_eventually_in V implies inf_net N is_eventually_in V )
consider f being Function of N,R such that
A1:
inf_net N = N *' f
and
A2:
for i being Element of N holds f . i = "/\" ( { (N . k) where k is Element of N : k >= i } ,R)
by Def4;
A3:
RelStr(# the carrier of (inf_net N), the InternalRel of (inf_net N) #) = RelStr(# the carrier of N, the InternalRel of N #)
by A1, Def3;
assume
N is_eventually_in V
; inf_net N is_eventually_in V
then consider i being Element of N such that
A4:
for j being Element of N st i <= j holds
N . j in V
;
reconsider i9 = i as Element of (inf_net N) by A3;
take
i9
; WAYBEL_0:def 11 for b1 being Element of the carrier of (inf_net N) holds
( not i9 <= b1 or (inf_net N) . b1 in V )
let j be Element of (inf_net N); ( not i9 <= j or (inf_net N) . j in V )
assume A5:
i9 <= j
; (inf_net N) . j in V
reconsider j0 = j as Element of N by A3;
defpred S1[ Element of N] means $1 >= j0;
deffunc H1( Element of N) -> Element of the carrier of R = N . $1;
set E = { H1(k) where k is Element of N : S1[k] } ;
consider j1 being Element of N such that
A6:
j1 >= j0
and
j1 >= j0
by YELLOW_6:def 3;
{ H1(k) where k is Element of N : S1[k] } is Subset of R
from DOMAIN_1:sch 8();
then reconsider E = { H1(k) where k is Element of N : S1[k] } as Subset of R ;
i <= j0
by A3, A5, YELLOW_0:1;
then
i <= j1
by A6, YELLOW_0:def 2;
then A7:
N . j1 in V
by A4;
N . j1 in E
by A6;
then A8:
"/\" (E,R) <= N . j1
by Th8;
the mapping of (inf_net N) = f
by A1, Def3;
then
(inf_net N) . j = "/\" (E,R)
by A2;
hence
(inf_net N) . j in V
by A7, A8, WAYBEL_0:def 19; verum