let S be non empty non void ManySortedSign ; :: thesis: for I being non empty finite set
for A being non-empty MSAlgebra of S
for F being MSAlgebra-Family of I,S st ( for i being Element of I ex C being strict non-empty finitely-generated MSSubAlgebra of A st C = F . i ) holds
ex B being strict non-empty finitely-generated MSSubAlgebra of A st
for i being Element of I holds F . i is MSSubAlgebra of B
let I be non empty finite set ; :: thesis: for A being non-empty MSAlgebra of S
for F being MSAlgebra-Family of I,S st ( for i being Element of I ex C being strict non-empty finitely-generated MSSubAlgebra of A st C = F . i ) holds
ex B being strict non-empty finitely-generated MSSubAlgebra of A st
for i being Element of I holds F . i is MSSubAlgebra of B
let A be non-empty MSAlgebra of S; :: thesis: for F being MSAlgebra-Family of I,S st ( for i being Element of I ex C being strict non-empty finitely-generated MSSubAlgebra of A st C = F . i ) holds
ex B being strict non-empty finitely-generated MSSubAlgebra of A st
for i being Element of I holds F . i is MSSubAlgebra of B
let F be MSAlgebra-Family of I,S; :: thesis: ( ( for i being Element of I ex C being strict non-empty finitely-generated MSSubAlgebra of A st C = F . i ) implies ex B being strict non-empty finitely-generated MSSubAlgebra of A st
for i being Element of I holds F . i is MSSubAlgebra of B )
assume A1:
for i being Element of I ex C being strict non-empty finitely-generated MSSubAlgebra of A st C = F . i
; :: thesis: ex B being strict non-empty finitely-generated MSSubAlgebra of A st
for i being Element of I holds F . i is MSSubAlgebra of B
set J = the carrier of S;
set Z = { C where C is Element of MSSub A : ex i being Element of I ex D being strict non-empty finitely-generated MSSubAlgebra of A st
( C = F . i & C = D ) } ;
consider m being Element of I;
consider W being strict non-empty finitely-generated MSSubAlgebra of A such that
A2:
W = F . m
by A1;
W is Element of MSSub A
by MSUALG_2:def 20;
then
W in { C where C is Element of MSSub A : ex i being Element of I ex D being strict non-empty finitely-generated MSSubAlgebra of A st
( C = F . i & C = D ) }
by A2;
then reconsider Z = { C where C is Element of MSSub A : ex i being Element of I ex D being strict non-empty finitely-generated MSSubAlgebra of A st
( C = F . i & C = D ) } as non empty set ;
defpred S1[ set , set ] means ex Q being strict non-empty MSSubAlgebra of A ex G being GeneratorSet of Q st
( $1 = Q & $2 = G & G is non-empty & G is finite-yielding );
A3:
for a being Element of Z ex b being Element of Bool the Sorts of A st S1[a,b]
consider f being Function of Z,(Bool the Sorts of A) such that
A10:
for B being Element of Z holds S1[B,f . B]
from FUNCT_2:sch 3(A3);
deffunc H1( set ) -> set = union { a where a is Element of bool (the Sorts of A . $1) : ex i being Element of I ex K being ManySortedSet of st
( K = f . (F . i) & a = K . $1 ) } ;
consider SOR being ManySortedSet of such that
A11:
for j being set st j in the carrier of S holds
SOR . j = H1(j)
from PBOOLE:sch 4();
SOR is ManySortedSubset of the Sorts of A
then reconsider SOR = SOR as MSSubset of A ;
SOR is non-empty
then reconsider SOR = SOR as V2() MSSubset of A ;
SOR is finite-yielding
then reconsider SOR = SOR as V2() V26() MSSubset of A ;
take B = GenMSAlg SOR; :: thesis: for i being Element of I holds F . i is MSSubAlgebra of B
let i be Element of I; :: thesis: F . i is MSSubAlgebra of B
consider C being strict non-empty finitely-generated MSSubAlgebra of A such that
A46:
C = F . i
by A1;
C is Element of MSSub A
by MSUALG_2:def 20;
then
F . i in Z
by A46;
then consider Q being strict non-empty MSSubAlgebra of A, G being GeneratorSet of Q such that
A47:
F . i = Q
and
A48:
( f . (F . i) = G & G is non-empty & G is finite-yielding )
by A10;
A49:
G c= the Sorts of Q
by PBOOLE:def 23;
the Sorts of Q is MSSubset of A
by MSUALG_2:def 10;
then
the Sorts of Q c= the Sorts of A
by PBOOLE:def 23;
then A50:
G c= the Sorts of A
by A49, PBOOLE:15;
then reconsider G1 = G as V2() MSSubset of A by A48, PBOOLE:def 23;
A51:
G1 is ManySortedSubset of SOR
C =
GenMSAlg G
by A46, A47, MSAFREE:3
.=
GenMSAlg G1
by EXTENS_1:22
;
hence
F . i is MSSubAlgebra of B
by A46, A51, EXTENS_1:21; :: thesis: verum