let X, Y be non empty set ; for D being Subset of X
for I1, I2 being Function of X,Y
for J1, J2 being Function of [:X,Y,Y:],Y
for E1, E2 being Function of X,X st E1,E2 is_well_founded_with_minimal_set D holds
ex f, g being continuous Function of (FlatPoset X),(FlatPoset Y) st
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
let D be Subset of X; for I1, I2 being Function of X,Y
for J1, J2 being Function of [:X,Y,Y:],Y
for E1, E2 being Function of X,X st E1,E2 is_well_founded_with_minimal_set D holds
ex f, g being continuous Function of (FlatPoset X),(FlatPoset Y) st
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
let I1, I2 be Function of X,Y; for J1, J2 being Function of [:X,Y,Y:],Y
for E1, E2 being Function of X,X st E1,E2 is_well_founded_with_minimal_set D holds
ex f, g being continuous Function of (FlatPoset X),(FlatPoset Y) st
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
let J1, J2 be Function of [:X,Y,Y:],Y; for E1, E2 being Function of X,X st E1,E2 is_well_founded_with_minimal_set D holds
ex f, g being continuous Function of (FlatPoset X),(FlatPoset Y) st
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
let E1, E2 be Function of X,X; ( E1,E2 is_well_founded_with_minimal_set D implies ex f, g being continuous Function of (FlatPoset X),(FlatPoset Y) st
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) ) )
assume A1:
E1,E2 is_well_founded_with_minimal_set D
; ex f, g being continuous Function of (FlatPoset X),(FlatPoset Y) st
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
A2:
( not X in X & not Y in Y )
;
set FX = FlatPoset X;
set CX = succ X;
set FY = FlatPoset Y;
set CY = succ Y;
consider f, g being set such that
A7:
( f in ConFuncs ((FlatPoset X),(FlatPoset Y)) & g in ConFuncs ((FlatPoset X),(FlatPoset Y)) & f = RecFunc02 (f,g,E1,E2,I1,J1,D) & g = RecFunc02 (f,g,E1,E2,I2,J2,D) )
by Threcursive0201;
reconsider f = f, g = g as continuous Function of (FlatPoset X),(FlatPoset Y) by A7;
take
f
; ex g being continuous Function of (FlatPoset X),(FlatPoset Y) st
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
take
g
; for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
consider l being Function of X,NAT such that
A801:
for x0 being Element of X holds
( ( l . x0 <= 0 implies x0 in D ) & ( not x0 in D implies ( l . (E1 . x0) < l . x0 & l . (E2 . x0) < l . x0 ) ) )
by A1;
defpred S1[ Nat] means for x1, x2 being Element of X st l . x1 <= $1 & l . x2 <= $1 holds
( f . x1 in Y & f . x1 = BaseFunc02 (x1,(f . (E1 . x1)),(g . (E2 . x1)),I1,J1,D) & g . x2 in Y & g . x2 = BaseFunc02 (x2,(f . (E1 . x2)),(g . (E2 . x2)),I2,J2,D) );
A9:
S1[ 0 ]
proof
let x1,
x2 be
Element of
X;
( l . x1 <= 0 & l . x2 <= 0 implies ( f . x1 in Y & f . x1 = BaseFunc02 (x1,(f . (E1 . x1)),(g . (E2 . x1)),I1,J1,D) & g . x2 in Y & g . x2 = BaseFunc02 (x2,(f . (E1 . x2)),(g . (E2 . x2)),I2,J2,D) ) )
assume b1:
(
l . x1 <= 0 &
l . x2 <= 0 )
;
( f . x1 in Y & f . x1 = BaseFunc02 (x1,(f . (E1 . x1)),(g . (E2 . x1)),I1,J1,D) & g . x2 in Y & g . x2 = BaseFunc02 (x2,(f . (E1 . x2)),(g . (E2 . x2)),I2,J2,D) )
B2:
(
x1 in X &
x2 in X )
;
reconsider x1 =
x1,
x2 =
x2 as
Element of
(FlatPoset X) by XBOOLE_0:def 3;
(
x1 <> X &
x2 <> X )
by B2;
then B4:
(
f . ((Flatten E1) . x1) = f . (E1 . x1) &
g . ((Flatten E2) . x1) = g . (E2 . x1) &
f . ((Flatten E1) . x2) = f . (E1 . x2) &
g . ((Flatten E2) . x2) = g . (E2 . x2) )
by DefFlatten04;
f . x1 = BaseFunc02 (
x1,
(f . (E1 . x1)),
(g . (E2 . x1)),
I1,
J1,
D)
by A7, DefRecFunc02, B4;
then B6:
f . x1 = I1 . x1
by DefBaseFunc02, b1, A801;
g . x2 = BaseFunc02 (
x2,
(f . (E1 . x2)),
(g . (E2 . x2)),
I2,
J2,
D)
by A7, DefRecFunc02, B4;
then
g . x2 = I2 . x2
by DefBaseFunc02, b1, A801;
hence
(
f . x1 in Y &
f . x1 = BaseFunc02 (
x1,
(f . (E1 . x1)),
(g . (E2 . x1)),
I1,
J1,
D) &
g . x2 in Y &
g . x2 = BaseFunc02 (
x2,
(f . (E1 . x2)),
(g . (E2 . x2)),
I2,
J2,
D) )
by A7, DefRecFunc02, B4, FUNCT_2:5, B6;
verum
end;
A10:
for k being Nat st S1[k] holds
S1[k + 1]
proof
let k be
Nat;
( S1[k] implies S1[k + 1] )
assume B0:
S1[
k]
;
S1[k + 1]
let x01,
x02 be
Element of
X;
( l . x01 <= k + 1 & l . x02 <= k + 1 implies ( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) ) )
assume B1:
(
l . x01 <= k + 1 &
l . x02 <= k + 1 )
;
( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) )
reconsider x01 =
x01,
x02 =
x02 as
Element of
(FlatPoset X) by XBOOLE_0:def 3;
(
x01 <> X &
x02 <> X )
by A2;
then B4:
(
f . ((Flatten E1) . x01) = f . (E1 . x01) &
g . ((Flatten E2) . x01) = g . (E2 . x01) &
f . ((Flatten E1) . x02) = f . (E1 . x02) &
g . ((Flatten E2) . x02) = g . (E2 . x02) )
by DefFlatten04;
set x11 =
E1 . x01;
set x21 =
E2 . x01;
set x12 =
E1 . x02;
set x22 =
E2 . x02;
reconsider x11 =
E1 . x01,
x12 =
E1 . x02,
x21 =
E2 . x01,
x22 =
E2 . x02 as
Element of
X by FUNCT_2:5;
B501:
f . x01 = BaseFunc02 (
x01,
(f . x11),
(g . x21),
I1,
J1,
D)
by A7, DefRecFunc02, B4;
B502:
g . x02 = BaseFunc02 (
x02,
(f . x12),
(g . x22),
I2,
J2,
D)
by A7, DefRecFunc02, B4;
reconsider x01 =
x01,
x02 =
x02 as
Element of
X ;
per cases
( x01 in D or not x01 in D )
;
suppose
x01 in D
;
( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) )then C2:
f . x01 = I1 . x01
by DefBaseFunc02, B501;
per cases
( x02 in D or not x02 in D )
;
suppose
x02 in D
;
( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) )then
g . x02 = I2 . x02
by DefBaseFunc02, B502;
hence
(
f . x01 in Y &
f . x01 = BaseFunc02 (
x01,
(f . (E1 . x01)),
(g . (E2 . x01)),
I1,
J1,
D) &
g . x02 in Y &
g . x02 = BaseFunc02 (
x02,
(f . (E1 . x02)),
(g . (E2 . x02)),
I2,
J2,
D) )
by C2, A7, DefRecFunc02, B4;
verum end; suppose C01:
not
x02 in D
;
( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) )then
(
(l . x12) + 1
<= l . x02 &
(l . x22) + 1
<= l . x02 )
by NAT_1:13, A801;
then
(
(l . x12) + 1
<= k + 1 &
(l . x22) + 1
<= k + 1 )
by B1, XXREAL_0:2;
then
(
l . x12 <= k &
l . x22 <= k )
by XREAL_1:8;
then C04:
(
f . x12 in Y &
g . x22 in Y )
by B0;
C06:
g . x02 = J2 . [x02,(f . x12),(g . x22)]
by B502, DefBaseFunc02, C01, C04;
[x02,(f . x12),(g . x22)] in [:X,Y,Y:]
by C04, MCART_1:69;
hence
(
f . x01 in Y &
f . x01 = BaseFunc02 (
x01,
(f . (E1 . x01)),
(g . (E2 . x01)),
I1,
J1,
D) &
g . x02 in Y &
g . x02 = BaseFunc02 (
x02,
(f . (E1 . x02)),
(g . (E2 . x02)),
I2,
J2,
D) )
by C2, C06, A7, DefRecFunc02, B4, FUNCT_2:5;
verum end; end; end; suppose C1:
not
x01 in D
;
( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) )then
(
(l . x11) + 1
<= l . x01 &
(l . x21) + 1
<= l . x01 )
by NAT_1:13, A801;
then
(
(l . x11) + 1
<= k + 1 &
(l . x21) + 1
<= k + 1 )
by B1, XXREAL_0:2;
then
(
l . x11 <= k &
l . x21 <= k )
by XREAL_1:8;
then C4:
(
f . x11 in Y &
g . x21 in Y )
by B0;
then C6:
f . x01 = J1 . [x01,(f . x11),(g . x21)]
by B501, DefBaseFunc02, C1;
C7:
[x01,(f . x11),(g . x21)] in [:X,Y,Y:]
by C4, MCART_1:69;
per cases
( x02 in D or not x02 in D )
;
suppose
x02 in D
;
( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) )then
g . x02 = I2 . x02
by DefBaseFunc02, B502;
hence
(
f . x01 in Y &
f . x01 = BaseFunc02 (
x01,
(f . (E1 . x01)),
(g . (E2 . x01)),
I1,
J1,
D) &
g . x02 in Y &
g . x02 = BaseFunc02 (
x02,
(f . (E1 . x02)),
(g . (E2 . x02)),
I2,
J2,
D) )
by C6, C7, FUNCT_2:5, A7, DefRecFunc02, B4;
verum end; suppose C01:
not
x02 in D
;
( f . x01 in Y & f . x01 = BaseFunc02 (x01,(f . (E1 . x01)),(g . (E2 . x01)),I1,J1,D) & g . x02 in Y & g . x02 = BaseFunc02 (x02,(f . (E1 . x02)),(g . (E2 . x02)),I2,J2,D) )then
(
(l . x12) + 1
<= l . x02 &
(l . x22) + 1
<= l . x02 )
by NAT_1:13, A801;
then
(
(l . x12) + 1
<= k + 1 &
(l . x22) + 1
<= k + 1 )
by B1, XXREAL_0:2;
then
(
l . x12 <= k &
l . x22 <= k )
by XREAL_1:8;
then C04:
(
f . x12 in Y &
g . x22 in Y )
by B0;
C06:
g . x02 = J2 . [x02,(f . x12),(g . x22)]
by B502, DefBaseFunc02, C01, C04;
[x02,(f . x12),(g . x22)] in [:X,Y,Y:]
by C04, MCART_1:69;
hence
(
f . x01 in Y &
f . x01 = BaseFunc02 (
x01,
(f . (E1 . x01)),
(g . (E2 . x01)),
I1,
J1,
D) &
g . x02 in Y &
g . x02 = BaseFunc02 (
x02,
(f . (E1 . x02)),
(g . (E2 . x02)),
I2,
J2,
D) )
by C6, C7, C06, A7, DefRecFunc02, B4, FUNCT_2:5;
verum end; end; end; end;
end;
A11:
for k being Nat holds S1[k]
from NAT_1:sch 2(A9, A10);
for x1, x2 being Element of X holds
( f . x1 in Y & f . x1 = BaseFunc02 (x1,(f . (E1 . x1)),(g . (E2 . x1)),I1,J1,D) & g . x2 in Y & g . x2 = BaseFunc02 (x2,(f . (E1 . x2)),(g . (E2 . x2)),I2,J2,D) )
proof
let x1,
x2 be
Element of
X;
( f . x1 in Y & f . x1 = BaseFunc02 (x1,(f . (E1 . x1)),(g . (E2 . x1)),I1,J1,D) & g . x2 in Y & g . x2 = BaseFunc02 (x2,(f . (E1 . x2)),(g . (E2 . x2)),I2,J2,D) )
reconsider k =
(l . x1) + (l . x2) as
Nat ;
(
l . x1 <= k &
l . x2 <= k )
by NAT_1:11;
hence
(
f . x1 in Y &
f . x1 = BaseFunc02 (
x1,
(f . (E1 . x1)),
(g . (E2 . x1)),
I1,
J1,
D) &
g . x2 in Y &
g . x2 = BaseFunc02 (
x2,
(f . (E1 . x2)),
(g . (E2 . x2)),
I2,
J2,
D) )
by A11;
verum
end;
hence
for x being Element of X holds
( f . x in Y & f . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I1,J1,D) & g . x in Y & g . x = BaseFunc02 (x,(f . (E1 . x)),(g . (E2 . x)),I2,J2,D) )
; verum