let S, E be non void Signature; :: thesis: for A being non-empty disjoint_valued MSAlgebra of S st A is MSAlgebra of E holds
ManySortedSign(# the carrier of S,the carrier' of S,the Arity of S,the ResultSort of S #) = ManySortedSign(# the carrier of E,the carrier' of E,the Arity of E,the ResultSort of E #)

let A be non-empty disjoint_valued MSAlgebra of S; :: thesis: ( A is MSAlgebra of E implies ManySortedSign(# the carrier of S,the carrier' of S,the Arity of S,the ResultSort of S #) = ManySortedSign(# the carrier of E,the carrier' of E,the Arity of E,the ResultSort of E #) )
assume A1: A is MSAlgebra of E ; :: thesis: ManySortedSign(# the carrier of S,the carrier' of S,the Arity of S,the ResultSort of S #) = ManySortedSign(# the carrier of E,the carrier' of E,the Arity of E,the ResultSort of E #)
then reconsider B = A as MSAlgebra of E ;
A2: ( the carrier of S = the carrier of E & the carrier' of S = the carrier' of E ) by A1, Th62;
A3: ( the Sorts of A is one-to-one & dom the Sorts of A = the carrier of S ) by Th63, PARTFUN1:def 4;
A4: ( dom the ResultSort of S = the carrier' of S & dom the ResultSort of E = the carrier' of E ) by FUNCT_2:def 1;
now
let x be set ; :: thesis: ( x in the carrier' of S implies the ResultSort of S . x = the ResultSort of E . x )
assume x in the carrier' of S ; :: thesis: the ResultSort of S . x = the ResultSort of E . x
then reconsider o = x as OperSymbol of S ;
reconsider e = o as OperSymbol of E by A1, Th62;
consider p being Element of Args o,A;
( Den o,A = the Charact of A . o & Den e,B = the Charact of B . e ) ;
then ( rng (Den o,A) c= Result o,A & rng (Den o,A) c= Result e,B & (Den o,A) . p in rng (Den o,A) ) by FUNCT_2:6, RELAT_1:def 19;
then Result o,A meets Result e,B by XBOOLE_0:3;
then Result o,A = (the Sorts of B * the ResultSort of E) . x by Th64
.= the Sorts of B . (the ResultSort of E . e) by FUNCT_2:21 ;
then the Sorts of A . (the ResultSort of E . e) = the Sorts of A . (the ResultSort of S . o) by FUNCT_2:21;
hence the ResultSort of S . x = the ResultSort of E . x by A2, A3, FUNCT_1:def 8; :: thesis: verum
end;
then A5: the ResultSort of S = the ResultSort of E by A1, Th62, A4, FUNCT_1:9;
A6: ( dom the Arity of S = the carrier' of S & dom the Arity of E = the carrier' of E ) by FUNCT_2:def 1;
now
let x be set ; :: thesis: ( x in the carrier' of S implies the Arity of S . x = the Arity of E . x )
assume x in the carrier' of S ; :: thesis: the Arity of S . x = the Arity of E . x
then reconsider o = x as OperSymbol of S ;
reconsider e = o as OperSymbol of E by A1, Th62;
reconsider p = the Arity of E . e as Element of the carrier of E * ;
reconsider q = the Arity of S . o as Element of the carrier of S * ;
( Den o,A = the Charact of A . o & Den e,B = the Charact of B . e & Result e,B is Component of the Sorts of A ) ;
then ( dom (Den o,A) = Args o,A & dom (Den o,A) = Args e,B ) by FUNCT_2:def 1;
then Args o,A = (the Sorts of B # ) . p by FUNCT_2:21
.= product (the Sorts of B * p) by PBOOLE:def 19 ;
then product (the Sorts of A * p) = (the Sorts of A # ) . q by FUNCT_2:21
.= product (the Sorts of A * q) by PBOOLE:def 19 ;
then A7: the Sorts of B * p = the Sorts of A * q by PUA2MSS1:2;
A8: ( rng p c= the carrier of E & rng q c= the carrier of S ) ;
then ( dom (the Sorts of B * p) = dom p & dom (the Sorts of A * q) = dom q ) by A2, A3, RELAT_1:46;
hence the Arity of S . x = the Arity of E . x by A2, A3, A7, A8, FUNCT_1:49; :: thesis: verum
end;
hence ManySortedSign(# the carrier of S,the carrier' of S,the Arity of S,the ResultSort of S #) = ManySortedSign(# the carrier of E,the carrier' of E,the Arity of E,the ResultSort of E #) by A2, A5, A6, FUNCT_1:9; :: thesis: verum