let Y, X be non empty set ; :: thesis: for F, G being BinOp of Y st F is idempotent & F is commutative & F is associative & G is_distributive_wrt F holds
for B being Element of Fin X st B <> {} holds
for f being Function of X,Y
for a being Element of Y holds G . (F $$ B,f),a = F $$ B,(G [:] f,a)
let F, G be BinOp of Y; :: thesis: ( F is idempotent & F is commutative & F is associative & G is_distributive_wrt F implies for B being Element of Fin X st B <> {} holds
for f being Function of X,Y
for a being Element of Y holds G . (F $$ B,f),a = F $$ B,(G [:] f,a) )
assume that
A1:
( F is idempotent & F is commutative & F is associative )
and
A2:
G is_distributive_wrt F
; :: thesis: for B being Element of Fin X st B <> {} holds
for f being Function of X,Y
for a being Element of Y holds G . (F $$ B,f),a = F $$ B,(G [:] f,a)
let B be Element of Fin X; :: thesis: ( B <> {} implies for f being Function of X,Y
for a being Element of Y holds G . (F $$ B,f),a = F $$ B,(G [:] f,a) )
assume A3:
B <> {}
; :: thesis: for f being Function of X,Y
for a being Element of Y holds G . (F $$ B,f),a = F $$ B,(G [:] f,a)
let f be Function of X,Y; :: thesis: for a being Element of Y holds G . (F $$ B,f),a = F $$ B,(G [:] f,a)
let a be Element of Y; :: thesis: G . (F $$ B,f),a = F $$ B,(G [:] f,a)
defpred S1[ Element of Fin X] means G . (F $$ $1,f),a = F $$ $1,(G [:] f,a);
A4:
for x being Element of X holds S1[{.x.}]
A5:
for B1, B2 being non empty Element of Fin X st S1[B1] & S1[B2] holds
S1[B1 \/ B2]
proof
let B1,
B2 be non
empty Element of
Fin X;
:: thesis: ( S1[B1] & S1[B2] implies S1[B1 \/ B2] )
assume that A7:
G . (F $$ B1,f),
a = F $$ B1,
(G [:] f,a)
and A8:
G . (F $$ B2,f),
a = F $$ B2,
(G [:] f,a)
;
:: thesis: S1[B1 \/ B2]
thus G . (F $$ (B1 \/ B2),f),
a =
G . (F . (F $$ B1,f),(F $$ B2,f)),
a
by A1, Th30
.=
F . (F $$ B1,(G [:] f,a)),
(F $$ B2,(G [:] f,a))
by A2, A7, A8, BINOP_1:23
.=
F $$ (B1 \/ B2),
(G [:] f,a)
by A1, Th30
;
:: thesis: verum
end;
for B being non empty Element of Fin X holds S1[B]
from SETWISEO:sch 3(A4, A5);
hence
G . (F $$ B,f),a = F $$ B,(G [:] f,a)
by A3; :: thesis: verum