let D be non empty set ; for A being Matrix of D
for P, Q being finite without_zero Subset of NAT holds
not ( [:P,Q:] c= Indices A & ( card P = 0 implies card Q = 0 ) & ( card Q = 0 implies card P = 0 ) & not (Segm (A,P,Q)) @ = Segm ((A @),Q,P) )
let A be Matrix of D; for P, Q being finite without_zero Subset of NAT holds
not ( [:P,Q:] c= Indices A & ( card P = 0 implies card Q = 0 ) & ( card Q = 0 implies card P = 0 ) & not (Segm (A,P,Q)) @ = Segm ((A @),Q,P) )
let P, Q be finite without_zero Subset of NAT; not ( [:P,Q:] c= Indices A & ( card P = 0 implies card Q = 0 ) & ( card Q = 0 implies card P = 0 ) & not (Segm (A,P,Q)) @ = Segm ((A @),Q,P) )
assume that
A1:
[:P,Q:] c= Indices A
and
A2:
( card P = 0 iff card Q = 0 )
; (Segm (A,P,Q)) @ = Segm ((A @),Q,P)
ex m being Nat st Q c= Seg m
by Th43;
then A3:
rng (Sgm Q) = Q
by FINSEQ_1:def 13;
ex n being Nat st P c= Seg n
by Th43;
then
rng (Sgm P) = P
by FINSEQ_1:def 13;
hence
(Segm (A,P,Q)) @ = Segm ((A @),Q,P)
by A1, A2, A3, Th18; verum