let L be complete algebraic LATTICE; :: thesis: for p being Element of L st p is completely-irreducible holds
p = "/\" { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) } ,L
let p be Element of L; :: thesis: ( p is completely-irreducible implies p = "/\" { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) } ,L )
set A = { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) } ;
assume
p is completely-irreducible
; :: thesis: p = "/\" { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) } ,L
then consider q being Element of L such that
A1:
p < q
and
A2:
for s being Element of L st p < s holds
q <= s
and
uparrow p = {p} \/ (uparrow q)
by Th20;
p <= q
by A1, ORDERS_2:def 10;
then A3:
compactbelow p c= compactbelow q
by WAYBEL13:1;
compactbelow p <> compactbelow q
then
not compactbelow q c= compactbelow p
by A3, XBOOLE_0:def 10;
then consider k1 being set such that
A4:
k1 in compactbelow q
and
A5:
not k1 in compactbelow p
by TARSKI:def 3;
k1 in { y where y is Element of L : ( q >= y & y is compact ) }
by A4, WAYBEL_8:def 2;
then consider k being Element of L such that
A6:
k = k1
and
A7:
q >= k
and
A8:
k is compact
;
A9:
k in the carrier of (CompactSublatt L)
by A8, WAYBEL_8:def 1;
p <= p
;
then A10:
p in uparrow p
by WAYBEL_0:18;
not k <= p
by A5, A6, A8, WAYBEL_8:4;
then
not p in uparrow k
by WAYBEL_0:18;
then A11:
p in the carrier of L \ (uparrow k)
by XBOOLE_0:def 5;
for y being Element of L holds
( not y in the carrier of L \ (uparrow k) or not p < y )
then
p is_maximal_in the carrier of L \ (uparrow k)
by A11, WAYBEL_4:56;
then A14:
p in { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) }
by A9, A10;
then A17:
p is_<=_than { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) }
by LATTICE3:def 8;
for u being Element of L st u is_<=_than { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) } holds
p >= u
by A14, LATTICE3:def 8;
hence
p = "/\" { x where x is Element of L : ( x in uparrow p & ex k being Element of L st
( k in the carrier of (CompactSublatt L) & x is_maximal_in the carrier of L \ (uparrow k) ) ) } ,L
by A17, YELLOW_0:33; :: thesis: verum