let Omega be non empty set ; for Sigma being SigmaField of Omega
for I being non empty Subset of REAL st I = {1,2,3} & Sigma = bool {1,2,3,4} & Omega = {1,2,3,4} holds
ex MyFunc being ManySortedSigmaField of I,Sigma st
( MyFunc . 1 = Special_SigmaField1 & MyFunc . 2 = Special_SigmaField2 & MyFunc . 3 = Special_SigmaField3 & MyFunc is Filtration of I,Sigma )
let Sigma be SigmaField of Omega; for I being non empty Subset of REAL st I = {1,2,3} & Sigma = bool {1,2,3,4} & Omega = {1,2,3,4} holds
ex MyFunc being ManySortedSigmaField of I,Sigma st
( MyFunc . 1 = Special_SigmaField1 & MyFunc . 2 = Special_SigmaField2 & MyFunc . 3 = Special_SigmaField3 & MyFunc is Filtration of I,Sigma )
let I be non empty Subset of REAL; ( I = {1,2,3} & Sigma = bool {1,2,3,4} & Omega = {1,2,3,4} implies ex MyFunc being ManySortedSigmaField of I,Sigma st
( MyFunc . 1 = Special_SigmaField1 & MyFunc . 2 = Special_SigmaField2 & MyFunc . 3 = Special_SigmaField3 & MyFunc is Filtration of I,Sigma ) )
assume A0:
( I = {1,2,3} & Sigma = bool {1,2,3,4} & Omega = {1,2,3,4} )
; ex MyFunc being ManySortedSigmaField of I,Sigma st
( MyFunc . 1 = Special_SigmaField1 & MyFunc . 2 = Special_SigmaField2 & MyFunc . 3 = Special_SigmaField3 & MyFunc is Filtration of I,Sigma )
consider MyFunc being ManySortedSigmaField of I,Sigma such that
A1:
( MyFunc . 1 = Special_SigmaField1 & MyFunc . 2 = Special_SigmaField2 & MyFunc . 3 = Special_SigmaField3 )
by A0, Th3;
A3:
for s, t being Element of I st s <= t holds
MyFunc . s is Subset of (MyFunc . t)
for t being Element of I holds MyFunc . t c= Sigma
by A0;
then
MyFunc is Filtration of I,Sigma
by A3, Def2000;
hence
ex MyFunc being ManySortedSigmaField of I,Sigma st
( MyFunc . 1 = Special_SigmaField1 & MyFunc . 2 = Special_SigmaField2 & MyFunc . 3 = Special_SigmaField3 & MyFunc is Filtration of I,Sigma )
by A1; verum