let Ke, Ne be Subset of NAT; for F being Function of Ne,Ke st rng F is finite holds
ex I being Function of Ne,Ke ex P being Permutation of (rng F) st
( F = P * I & rng F = rng I & I is 'increasing )
defpred S1[ set , Function] means $1 = $2 . (min* (dom $2));
defpred S2[ set ] means for Ne, Ke being Subset of NAT
for F being Function of Ne,Ke st F = $1 & rng F is finite holds
ex P being Permutation of (rng F) ex G being Function of Ne,Ke st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) );
A1:
S2[ {} ]
proof
let Ne,
Me be
Subset of
NAT;
for F being Function of Ne,Me st F = {} & rng F is finite holds
ex P being Permutation of (rng F) ex G being Function of Ne,Me st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )let F be
Function of
Ne,
Me;
( F = {} & rng F is finite implies ex P being Permutation of (rng F) ex G being Function of Ne,Me st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) ) )
assume that A2:
F = {}
and
rng F is
finite
;
ex P being Permutation of (rng F) ex G being Function of Ne,Me st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )
reconsider R =
rng F as
empty set by A2;
set P =
{} ;
A3:
rng {} = {}
;
reconsider P =
{} as
Function of
R,
R by A3, FUNCT_2:1;
rng R = {}
;
then
(
P is
one-to-one &
P is
onto )
by FUNCT_2:def 3;
then reconsider P =
P as
Permutation of
(rng F) ;
take
P
;
ex G being Function of Ne,Me st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )
take
F
;
( F = P * F & rng F = rng F & ( for i, j being Nat st i in rng F & j in rng F & i < j holds
min* (F " {i}) < min* (F " {j}) ) )
rng F = R
;
then
F = {}
;
hence
(
F = P * F &
rng F = rng F & ( for
i,
j being
Nat st
i in rng F &
j in rng F &
i < j holds
min* (F " {i}) < min* (F " {j}) ) )
;
verum
end;
A4:
for F being Function st ( for x being set st x in rng F & S1[x,F] holds
S2[F | ((dom F) \ (F " {x}))] ) holds
S2[F]
proof
let F9 be
Function;
( ( for x being set st x in rng F9 & S1[x,F9] holds
S2[F9 | ((dom F9) \ (F9 " {x}))] ) implies S2[F9] )
assume A5:
for
x being
set st
x in rng F9 &
S1[
x,
F9] holds
S2[
F9 | ((dom F9) \ (F9 " {x}))]
;
S2[F9]
let N,
K be
Subset of
NAT;
for F being Function of N,K st F = F9 & rng F is finite holds
ex P being Permutation of (rng F) ex G being Function of N,K st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )let F be
Function of
N,
K;
( F = F9 & rng F is finite implies ex P being Permutation of (rng F) ex G being Function of N,K st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) ) )
assume that A6:
F = F9
and A7:
rng F is
finite
;
ex P being Permutation of (rng F) ex G being Function of N,K st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )
now ex P being Permutation of (rng F) ex G being Function of N,K st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )per cases
( rng F9 is empty or not rng F9 is empty )
;
suppose A8:
not
rng F9 is
empty
;
ex P being Permutation of (rng F) ex G being Function of N,K st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )then reconsider domF =
dom F as non
empty Subset of
NAT by A6, RELAT_1:42, XBOOLE_1:1;
reconsider K =
K as non
empty Subset of
NAT by A6, A8;
set m =
min* domF;
set D =
(dom F) \ (F " {(F . (min* domF))});
min* domF in domF
by NAT_1:def 1;
then A9:
F . (min* domF) in rng F
by FUNCT_1:def 3;
now ex P being Permutation of (rng F) ex G being Function of N,K st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )per cases
( rng (F | ((dom F) \ (F " {(F . (min* domF))}))) is empty or not rng (F | ((dom F) \ (F " {(F . (min* domF))}))) is empty )
;
suppose A15:
not
rng (F | ((dom F) \ (F " {(F . (min* domF))}))) is
empty
;
ex P being Permutation of (rng F) ex G being Function of N,K st
( F = P * G & rng F = rng G & ( for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j}) ) )
rng (F | ((dom F) \ (F " {(F . (min* domF))}))) c= rng F
by RELAT_1:70;
then reconsider rFD =
rng (F | ((dom F) \ (F " {(F . (min* domF))}))) as non
empty finite Subset of
NAT by A7, A15, XBOOLE_1:1;
deffunc H1(
set )
-> set =
F . (min* domF);
reconsider dFD =
dom (F | ((dom F) \ (F " {(F . (min* domF))}))) as
Subset of
NAT by XBOOLE_1:1;
reconsider FD =
F | ((dom F) \ (F " {(F . (min* domF))})) as
Function of
dFD,
rFD by FUNCT_2:1;
A16:
(
rFD is
empty implies
dFD is
empty )
;
reconsider rF =
rng F as non
empty finite Subset of
NAT by A7, A9, XBOOLE_1:1;
A17:
(
dFD c= N &
rFD c= K )
;
consider P being
Permutation of
(rng FD),
G being
Function of
dFD,
rFD such that A18:
FD = P * G
and A19:
rng FD = rng G
and A20:
for
i,
j being
Nat st
i in rng G &
j in rng G &
i < j holds
min* (G " {i}) < min* (G " {j})
by A5, A6, A9;
A21:
for
x being
set st
x in N \ dFD holds
H1(
x)
in K
by A9;
consider G2 being
Function of
N,
K such that A22:
(
G2 | dFD = G & ( for
x being
set st
x in N \ dFD holds
G2 . x = H1(
x) ) )
from STIRL2_1:sch 2(A21, A17, A16);
A23:
rng G2 c= rng F
proof
let Gx be
object ;
TARSKI:def 3 ( not Gx in rng G2 or Gx in rng F )
assume
Gx in rng G2
;
Gx in rng F
then consider x being
object such that A24:
x in dom G2
and A25:
G2 . x = Gx
by FUNCT_1:def 3;
dom G2 = N
by FUNCT_2:def 1;
then
((dom G2) /\ dFD) \/ (N \ dFD) = dom G2
by XBOOLE_1:51;
then
( (
dom G = (dom G2) /\ dFD &
x in (dom G2) /\ dFD ) or
x in N \ dFD )
by A22, A24, RELAT_1:61, XBOOLE_0:def 3;
then
( (
G . x in rng FD &
G . x = G2 . x &
rng FD = (rng F) \ {(F . (min* domF))} ) or (
G2 . x = F . (min* domF) &
min* domF in domF ) )
by A19, A22, Th54, FUNCT_1:47, FUNCT_1:def 3, NAT_1:def 1;
hence
Gx in rng F
by A25, FUNCT_1:def 3, XBOOLE_0:def 5;
verum
end; A26:
rng FD = (rng F) \ {(F . (min* domF))}
by Th54;
dom FD = (dom F) /\ ((dom F) \ (F " {(F . (min* domF))}))
by RELAT_1:61;
then A27:
dFD = (dom F) \ (F " {(F . (min* domF))})
by XBOOLE_1:28, XBOOLE_1:36;
A28:
F " {(F . (min* domF))} c= G2 " {(F . (min* domF))}
rng F c= rng G2
then A38:
rng G2 = rng F
by A23;
not
F . (min* domF) in (rng F) \ {(F . (min* domF))}
by ZFMISC_1:56;
then
not
F . (min* domF) in rng FD
by Th54;
then consider P2 being
Function of
((rng FD) \/ {(F . (min* domF))}),
((rng FD) \/ {(F . (min* domF))}) such that A39:
P2 | (rng FD) = P
and A40:
P2 . (F . (min* domF)) = F . (min* domF)
by Th57;
not
F . (min* domF) in (rng F) \ {(F . (min* domF))}
by ZFMISC_1:56;
then A41:
(
P2 is
one-to-one &
P2 is
onto )
by A39, A40, A26, Th58;
(rng FD) \/ {(F . (min* domF))} = rng F
by A9, A26, ZFMISC_1:116;
then reconsider P2 =
P2 as
Permutation of
(rng F) by A41;
consider Orde being
Function of
rF,
(Segm (card rF)) such that A42:
Orde is
bijective
and A43:
for
n,
k being
Nat st
n in dom Orde &
k in dom Orde &
n < k holds
Orde . n < Orde . k
by Th59;
rng Orde = card rF
by A42, FUNCT_2:def 3;
then reconsider Orde9 =
Orde " as
Function of
(card rF),
rF by A42, FUNCT_2:25;
consider P1 being
Permutation of
rF such that A44:
for
k being
Nat st
k in rF holds
( (
k < F . (min* domF) implies
P1 . k = (Orde ") . ((Orde . k) + 1) ) & (
k = F . (min* domF) implies
P1 . k = (Orde ") . 0 ) & (
k > F . (min* domF) implies
P1 . k = k ) )
by A9, A42, A43, Lm5;
dom G2 = N
by FUNCT_2:def 1;
then A45:
G2 is
Function of
N,
rF
by A38, FUNCT_2:1;
reconsider P21 =
P2 * (P1 ") as
Function of
rF,
rF ;
reconsider P21 =
P21 as
Permutation of
rF ;
dom P1 = rF
by FUNCT_2:def 1;
then A46:
(P1 ") * P1 = id rF
by FUNCT_1:39;
rng (P1 * G2) c= K
by XBOOLE_1:1;
then reconsider PG =
P1 * G2 as
Function of
N,
K by A45, FUNCT_2:6;
dom G2 = N
by FUNCT_2:def 1;
then
G2 is
Function of
N,
rF
by A38, FUNCT_2:1;
then
(id rF) * G2 = G2
by FUNCT_2:17;
then A47:
(P1 ") * (P1 * G2) = G2
by A46, RELAT_1:36;
G2 " {(F . (min* domF))} c= F " {(F . (min* domF))}
then A54:
G2 " {(F . (min* domF))} = F " {(F . (min* domF))}
by A28;
A55:
for
n being
Nat st
n in rng FD holds
G " {n} = G2 " {n}
A58:
for
i,
j being
Nat st
i in rng PG &
j in rng PG &
i < j holds
min* (PG " {i}) < min* (PG " {j})
proof
A59:
for
l being
Nat st
l in rF &
l < F . (min* domF) holds
(
(Orde . l) + 1
in rng Orde &
(Orde . l) + 1 is
Element of
NAT &
(Orde . l) + 1
<= Orde . (F . (min* domF)) &
Orde . (F . (min* domF)) is
Element of
NAT &
dom Orde = rF )
proof
A60:
dom Orde = rF
by FUNCT_2:def 1;
A61:
Orde . (F . (min* domF)) in card rF
;
A62:
Orde . (F . (min* domF)) < card rF
by NAT_1:44;
let l be
Nat;
( l in rF & l < F . (min* domF) implies ( (Orde . l) + 1 in rng Orde & (Orde . l) + 1 is Element of NAT & (Orde . l) + 1 <= Orde . (F . (min* domF)) & Orde . (F . (min* domF)) is Element of NAT & dom Orde = rF ) )
assume that A63:
l in rF
and A64:
l < F . (min* domF)
;
( (Orde . l) + 1 in rng Orde & (Orde . l) + 1 is Element of NAT & (Orde . l) + 1 <= Orde . (F . (min* domF)) & Orde . (F . (min* domF)) is Element of NAT & dom Orde = rF )
A65:
Orde . l < Orde . (F . (min* domF))
by A9, A43, A63, A64, A60;
then
(Orde . l) + 1
<= Orde . (F . (min* domF))
by NAT_1:13;
then A66:
(Orde . l) + 1
< card rF
by A62, XXREAL_0:2;
card rF = rng Orde
by A42, FUNCT_2:def 3;
hence
(
(Orde . l) + 1
in rng Orde &
(Orde . l) + 1 is
Element of
NAT &
(Orde . l) + 1
<= Orde . (F . (min* domF)) &
Orde . (F . (min* domF)) is
Element of
NAT &
dom Orde = rF )
by A65, A61, A66, FUNCT_2:def 1, NAT_1:13, NAT_1:44;
verum
end;
A67:
for
n,
k being
Nat st
n in dom Orde &
k in dom Orde &
Orde . n < Orde . k holds
n < k
A71:
for
n,
k being
Nat st
n in rng Orde &
k in rng Orde &
n < k holds
Orde9 . n < Orde9 . k
proof
let n,
k be
Nat;
( n in rng Orde & k in rng Orde & n < k implies Orde9 . n < Orde9 . k )
assume that A72:
n in rng Orde
and A73:
k in rng Orde
;
( not n < k or Orde9 . n < Orde9 . k )
A74:
n = Orde . (Orde9 . n)
by A42, A72, FUNCT_1:35;
A75:
dom Orde = rng Orde9
by A42, FUNCT_1:33;
A76:
k = Orde . (Orde9 . k)
by A42, A73, FUNCT_1:35;
assume A77:
n < k
;
Orde9 . n < Orde9 . k
A78:
rng Orde = dom Orde9
by A42, FUNCT_1:33;
then A79:
Orde9 . n in dom Orde
by A72, A75, FUNCT_1:def 3;
Orde9 . k in dom Orde
by A73, A78, A75, FUNCT_1:def 3;
hence
Orde9 . n < Orde9 . k
by A67, A77, A74, A76, A79;
verum
end;
rng FD = (rng F) \ {(F . (min* domF))}
by Th54;
then A80:
(rng FD) \/ {(F . (min* domF))} = rng G2
by A9, A38, ZFMISC_1:116;
let i,
j be
Nat;
( i in rng PG & j in rng PG & i < j implies min* (PG " {i}) < min* (PG " {j}) )
assume that A81:
i in rng PG
and A82:
j in rng PG
and A83:
i < j
;
min* (PG " {i}) < min* (PG " {j})
consider i1 being
set such that A84:
i1 in dom P1
and A85:
i1 in rng G2
and A86:
P1 " {i} = {i1}
and A87:
G2 " {i1} = PG " {i}
by A81, Th61;
consider j1 being
set such that A88:
j1 in dom P1
and A89:
j1 in rng G2
and A90:
P1 " {j} = {j1}
and A91:
G2 " {j1} = PG " {j}
by A82, Th61;
dom P1 = rF
by FUNCT_2:def 1;
then reconsider i1 =
i1,
j1 =
j1 as
Element of
NAT by A84, A88;
A92:
i1 in P1 " {i}
by A86, TARSKI:def 1;
then
P1 . i1 in {i}
by FUNCT_1:def 7;
then A93:
P1 . i1 = i
by TARSKI:def 1;
A94:
j1 in P1 " {j}
by A90, TARSKI:def 1;
then A95:
P1 . j1 in {j}
by FUNCT_1:def 7;
then A96:
P1 . j1 = j
by TARSKI:def 1;
A97:
dom Orde = rF
by FUNCT_2:def 1;
now min* (PG " {i}) < min* (PG " {j})per cases
( ( i1 < F . (min* domF) & j1 < F . (min* domF) ) or ( i1 = F . (min* domF) & j1 <> F . (min* domF) ) or ( i1 < F . (min* domF) & j1 = F . (min* domF) ) or ( i1 = F . (min* domF) & j1 = F . (min* domF) ) or ( i1 > F . (min* domF) & j1 > F . (min* domF) ) or ( i1 > F . (min* domF) & j1 = F . (min* domF) ) or ( i1 < F . (min* domF) & j1 > F . (min* domF) ) or ( i1 > F . (min* domF) & j1 < F . (min* domF) ) )
by XXREAL_0:1;
suppose A98:
(
i1 < F . (min* domF) &
j1 < F . (min* domF) )
;
min* (PG " {i}) < min* (PG " {j})A99:
(
i1 in rng FD or
i1 in {(F . (min* domF))} )
by A85, A80, XBOOLE_0:def 3;
then A100:
G " {i1} = PG " {i}
by A55, A87, A98, TARSKI:def 1;
A101:
(
j1 in rng FD or
j1 in {(F . (min* domF))} )
by A89, A80, XBOOLE_0:def 3;
i1 < j1
proof
assume
i1 >= j1
;
contradiction
then
i1 > j1
by A83, A93, A96, XXREAL_0:1;
then
Orde . i1 > Orde . j1
by A43, A92, A94, A97;
then A102:
(Orde . i1) + 1
> (Orde . j1) + 1
by XREAL_1:8;
A103:
(Orde . i1) + 1
in rng Orde
by A84, A59, A98;
A104:
Orde9 . ((Orde . j1) + 1) = j
by A44, A94, A96, A98;
A105:
(Orde . j1) + 1
in rng Orde
by A88, A59, A98;
Orde9 . ((Orde . i1) + 1) = i
by A44, A92, A93, A98;
hence
contradiction
by A83, A71, A102, A103, A105, A104;
verum
end; then
min* (G " {i1}) < min* (G " {j1})
by A19, A20, A98, A99, A101, TARSKI:def 1;
hence
min* (PG " {i}) < min* (PG " {j})
by A55, A91, A98, A101, A100, TARSKI:def 1;
verum end; suppose A106:
(
i1 = F . (min* domF) &
j1 <> F . (min* domF) )
;
min* (PG " {i}) < min* (PG " {j})consider x being
object such that A107:
x in dom G2
and A108:
G2 . x = j1
by A89, FUNCT_1:def 3;
G2 . x in {j1}
by A108, TARSKI:def 1;
then
PG " {j} is non
empty Subset of
NAT
by A91, A107, FUNCT_1:def 7, XBOOLE_1:1;
then A109:
min* (PG " {j}) in PG " {j}
by NAT_1:def 1;
(
j1 in rng FD or
j1 in {(F . (min* domF))} )
by A89, A80, XBOOLE_0:def 3;
then A110:
G " {j1} = PG " {j}
by A55, A91, A106, TARSKI:def 1;
then
min* (PG " {j}) in dom F
by A27, A109, XBOOLE_0:def 5;
then A111:
min* domF <= min* (PG " {j})
by NAT_1:def 1;
A112:
min* domF in domF
by NAT_1:def 1;
F . (min* domF) in {(F . (min* domF))}
by TARSKI:def 1;
then A113:
min* domF in F " {(F . (min* domF))}
by A112, FUNCT_1:def 7;
then
min* domF <> min* (PG " {j})
by A27, A110, A109, XBOOLE_0:def 5;
then A114:
min* domF < min* (PG " {j})
by A111, XXREAL_0:1;
PG " {i} is
Subset of
NAT
by XBOOLE_1:1;
then
min* (PG " {i}) <= min* domF
by A28, A87, A106, A113, NAT_1:def 1;
hence
min* (PG " {i}) < min* (PG " {j})
by A114, XXREAL_0:2;
verum end; suppose A115:
(
i1 < F . (min* domF) &
j1 = F . (min* domF) )
;
min* (PG " {i}) < min* (PG " {j})
card rF = rng Orde
by A42, FUNCT_2:def 3;
then A116:
0 in rng Orde
by NAT_1:44;
(Orde . i1) + 1
in rng Orde
by A84, A59, A115;
then A117:
Orde9 . ((Orde . i1) + 1) > Orde9 . 0
by A71, A116;
A118:
P1 . j1 = Orde9 . 0
by A44, A94, A115;
Orde9 . ((Orde . i1) + 1) = i
by A44, A92, A93, A115;
hence
min* (PG " {i}) < min* (PG " {j})
by A83, A95, A117, A118, TARSKI:def 1;
verum end; suppose A119:
(
i1 > F . (min* domF) &
j1 > F . (min* domF) )
;
min* (PG " {i}) < min* (PG " {j})A120:
(
i1 in rng FD or
i1 in {(F . (min* domF))} )
by A85, A80, XBOOLE_0:def 3;
then A121:
G " {i1} = PG " {i}
by A55, A87, A119, TARSKI:def 1;
A122:
P1 . j1 = j1
by A44, A88, A119;
A123:
(
j1 in rng FD or
j1 in {(F . (min* domF))} )
by A89, A80, XBOOLE_0:def 3;
P1 . i1 = i1
by A44, A84, A119;
then
min* (G " {i1}) < min* (G " {j1})
by A19, A20, A83, A93, A96, A119, A122, A120, A123, TARSKI:def 1;
hence
min* (PG " {i}) < min* (PG " {j})
by A55, A91, A119, A123, A121, TARSKI:def 1;
verum end; suppose A124:
(
i1 > F . (min* domF) &
j1 = F . (min* domF) )
;
min* (PG " {i}) < min* (PG " {j})A125:
dom Orde = rF
by FUNCT_2:def 1;
rng (Orde ") = dom Orde
by A42, FUNCT_1:33;
then consider x being
object such that A126:
x in dom Orde9
and A127:
Orde9 . x = i1
by A84, A125, FUNCT_1:def 3;
A128:
x in card rF
by A126;
card rF is
Subset of
NAT
by Th8;
then reconsider x =
x as
Element of
NAT by A128;
P1 . i1 = i1
by A44, A84, A124;
then A129:
Orde9 . x < Orde9 . 0
by A44, A83, A88, A93, A96, A124, A127;
A130:
card rF = rng Orde
by A42, FUNCT_2:def 3;
then
0 in rng Orde
by NAT_1:44;
then
x <= 0
by A71, A126, A130, A129;
hence
min* (PG " {i}) < min* (PG " {j})
by A129;
verum end; suppose A131:
(
i1 < F . (min* domF) &
j1 > F . (min* domF) )
;
min* (PG " {i}) < min* (PG " {j})A132:
(
i1 in rng FD or
i1 in {(F . (min* domF))} )
by A85, A80, XBOOLE_0:def 3;
then A133:
G " {i1} = PG " {i}
by A55, A87, A131, TARSKI:def 1;
A134:
(
j1 in rng FD or
j1 in {(F . (min* domF))} )
by A89, A80, XBOOLE_0:def 3;
i1 < j1
by A131, XXREAL_0:2;
then
min* (G " {i1}) < min* (G " {j1})
by A19, A20, A131, A132, A134, TARSKI:def 1;
hence
min* (PG " {i}) < min* (PG " {j})
by A55, A91, A131, A134, A133, TARSKI:def 1;
verum end; suppose A135:
(
i1 > F . (min* domF) &
j1 < F . (min* domF) )
;
min* (PG " {i}) < min* (PG " {j})then
dom Orde = rF
by A88, A59;
then A136:
Orde . (F . (min* domF)) in rng Orde
by A9, FUNCT_1:def 3;
(Orde . j1) + 1
<= Orde . (F . (min* domF))
by A88, A59, A135;
then A137:
(
(Orde . j1) + 1
< Orde . (F . (min* domF)) or
(Orde . j1) + 1
= Orde . (F . (min* domF)) )
by XXREAL_0:1;
F . (min* domF) in dom Orde
by A9, A88, A59, A135;
then A138:
Orde9 . (Orde . (F . (min* domF))) = F . (min* domF)
by A42, FUNCT_1:34;
A139:
P1 . i1 = i1
by A44, A84, A135;
A140:
Orde9 . ((Orde . j1) + 1) = P1 . j1
by A44, A88, A135;
(Orde . j1) + 1
in rng Orde
by A88, A59, A135;
then
P1 . j1 <= F . (min* domF)
by A71, A137, A136, A138, A140;
hence
min* (PG " {i}) < min* (PG " {j})
by A83, A93, A96, A135, A139, XXREAL_0:2;
verum end; end; end;
hence
min* (PG " {i}) < min* (PG " {j})
;
verum
end;
not
K is
empty
;
then A141:
dom F = N
by FUNCT_2:def 1;
A142:
for
x being
object st
x in dom F holds
F . x = P2 . (G2 . x)
proof
let x be
object ;
( x in dom F implies F . x = P2 . (G2 . x) )
assume A143:
x in dom F
;
F . x = P2 . (G2 . x)
now F . x = P2 . (G2 . x)per cases
( x in N \ dFD or x in dFD )
by A143, XBOOLE_0:def 5;
suppose A147:
x in dFD
;
F . x = P2 . (G2 . x)then A148:
F . x = FD . x
by FUNCT_1:47;
A149:
FD . x = P . (G . x)
by A18, A147, FUNCT_1:12;
A150:
dom P = rng FD
by FUNCT_2:def 1;
A151:
x in dom G
by A147, FUNCT_2:def 1;
then A152:
G . x in rng FD
by A19, FUNCT_1:def 3;
G . x = G2 . x
by A22, A151, FUNCT_1:47;
hence
F . x = P2 . (G2 . x)
by A39, A148, A149, A152, A150, FUNCT_1:47;
verum end; end; end;
hence
F . x = P2 . (G2 . x)
;
verum
end; A153:
dom G2 = N
by FUNCT_2:def 1;
for
x being
object holds
(
x in dom F iff (
x in dom G2 &
G2 . x in dom P2 ) )
then
F = P2 * G2
by A142, FUNCT_1:10;
then A155:
F = P21 * PG
by A47, RELAT_1:36;
rng P1 = rF
by FUNCT_2:def 3;
then
rng (P1 * G2) = rF
by A38, A45, FUNCT_2:14;
hence
ex
P being
Permutation of
(rng F) ex
G being
Function of
N,
K st
(
F = P * G &
rng F = rng G & ( for
i,
j being
Nat st
i in rng G &
j in rng G &
i < j holds
min* (G " {i}) < min* (G " {j}) ) )
by A155, A58;
verum end; end; end; hence
ex
P being
Permutation of
(rng F) ex
G being
Function of
N,
K st
(
F = P * G &
rng F = rng G & ( for
i,
j being
Nat st
i in rng G &
j in rng G &
i < j holds
min* (G " {i}) < min* (G " {j}) ) )
;
verum end; end; end;
hence
ex
P being
Permutation of
(rng F) ex
G being
Function of
N,
K st
(
F = P * G &
rng F = rng G & ( for
i,
j being
Nat st
i in rng G &
j in rng G &
i < j holds
min* (G " {i}) < min* (G " {j}) ) )
;
verum
end;
A156:
for F being Function st rng F is finite holds
S2[F]
from STIRL2_1:sch 7(A1, A4);
let F be Function of Ne,Ke; ( rng F is finite implies ex I being Function of Ne,Ke ex P being Permutation of (rng F) st
( F = P * I & rng F = rng I & I is 'increasing ) )
assume
rng F is finite
; ex I being Function of Ne,Ke ex P being Permutation of (rng F) st
( F = P * I & rng F = rng I & I is 'increasing )
then consider P being Permutation of (rng F), G being Function of Ne,Ke such that
A157:
F = P * G
and
A158:
rng F = rng G
and
A159:
for i, j being Nat st i in rng G & j in rng G & i < j holds
min* (G " {i}) < min* (G " {j})
by A156;
G is 'increasing
by A159;
hence
ex I being Function of Ne,Ke ex P being Permutation of (rng F) st
( F = P * I & rng F = rng I & I is 'increasing )
by A157, A158; verum