let n be Element of NAT ; :: thesis: for T being connected admissible TermOrder of n
for L being non empty non degenerated right_complementable almost_left_invertible associative commutative well-unital distributive Abelian add-associative right_zeroed doubleLoopStr
for P being Subset of (Polynom-Ring n,L) st HT (P -Ideal ),T c= multiples (HT P,T) holds
PolyRedRel P,T is locally-confluent

let T be connected admissible TermOrder of n; :: thesis: for L being non empty non degenerated right_complementable almost_left_invertible associative commutative well-unital distributive Abelian add-associative right_zeroed doubleLoopStr
for P being Subset of (Polynom-Ring n,L) st HT (P -Ideal ),T c= multiples (HT P,T) holds
PolyRedRel P,T is locally-confluent

let L be non empty non degenerated right_complementable almost_left_invertible associative commutative well-unital distributive Abelian add-associative right_zeroed doubleLoopStr ; :: thesis: for P being Subset of (Polynom-Ring n,L) st HT (P -Ideal ),T c= multiples (HT P,T) holds
PolyRedRel P,T is locally-confluent

let P be Subset of (Polynom-Ring n,L); :: thesis: ( HT (P -Ideal ),T c= multiples (HT P,T) implies PolyRedRel P,T is locally-confluent )
set R = PolyRedRel P,T;
assume A1: HT (P -Ideal ),T c= multiples (HT P,T) ; :: thesis: PolyRedRel P,T is locally-confluent
A2: for f being Polynomial of n,L st f in P -Ideal & f <> 0_ n,L holds
f is_reducible_wrt P,T
proof
let f be Polynomial of n,L; :: thesis: ( f in P -Ideal & f <> 0_ n,L implies f is_reducible_wrt P,T )
assume that
A3: f in P -Ideal and
A4: f <> 0_ n,L ; :: thesis: f is_reducible_wrt P,T
HT f,T in { (HT p,T) where p is Polynomial of n,L : ( p in P -Ideal & p <> 0_ n,L ) } by A3, A4;
then HT f,T in multiples (HT P,T) by A1;
then ex b being Element of Bags n st
( b = HT f,T & ex b9 being bag of n st
( b9 in HT P,T & b9 divides b ) ) ;
then consider b9 being bag of n such that
A5: b9 in HT P,T and
A6: b9 divides HT f,T ;
consider p being Polynomial of n,L such that
A7: b9 = HT p,T and
A8: p in P and
A9: p <> 0_ n,L by A5;
consider s being bag of n such that
A10: b9 + s = HT f,T by A6, TERMORD:1;
set g = f - (((f . (HT f,T)) / (HC p,T)) * (s *' p));
Support f <> {} by A4, POLYNOM7:1;
then HT f,T in Support f by TERMORD:def 6;
then f reduces_to f - (((f . (HT f,T)) / (HC p,T)) * (s *' p)),p, HT f,T,T by A4, A7, A9, A10, POLYRED:def 5;
then f reduces_to f - (((f . (HT f,T)) / (HC p,T)) * (s *' p)),p,T by POLYRED:def 6;
then f reduces_to f - (((f . (HT f,T)) / (HC p,T)) * (s *' p)),P,T by A8, POLYRED:def 7;
hence f is_reducible_wrt P,T by POLYRED:def 9; :: thesis: verum
end;
A11: for f being Polynomial of n,L st f in P -Ideal holds
PolyRedRel P,T reduces f, 0_ n,L
proof
let f be Polynomial of n,L; :: thesis: ( f in P -Ideal implies PolyRedRel P,T reduces f, 0_ n,L )
assume A12: f in P -Ideal ; :: thesis: PolyRedRel P,T reduces f, 0_ n,L
per cases ( f = 0_ n,L or f <> 0_ n,L ) ;
suppose f <> 0_ n,L ; :: thesis: PolyRedRel P,T reduces f, 0_ n,L
then f is_reducible_wrt P,T by A2, A12;
then consider v being Polynomial of n,L such that
A13: f reduces_to v,P,T by POLYRED:def 9;
[f,v] in PolyRedRel P,T by A13, POLYRED:def 13;
then f in field (PolyRedRel P,T) by RELAT_1:30;
then f has_a_normal_form_wrt PolyRedRel P,T by REWRITE1:def 14;
then consider g being set such that
A14: g is_a_normal_form_of f, PolyRedRel P,T by REWRITE1:def 11;
A15: PolyRedRel P,T reduces f,g by A14, REWRITE1:def 6;
then reconsider g9 = g as Polynomial of n,L by Lm4;
reconsider ff = f, gg = g9 as Element of (Polynom-Ring n,L) by POLYNOM1:def 27;
reconsider ff = ff, gg = gg as Element of (Polynom-Ring n,L) ;
f - g9 = ff - gg by Lm2;
then ff - gg in P -Ideal by A15, POLYRED:59;
then A16: (ff - gg) - ff in P -Ideal by A12, IDEAL_1:16;
(ff - gg) - ff = (ff + (- gg)) - ff by RLVECT_1:def 14
.= (ff + (- gg)) + (- ff) by RLVECT_1:def 14
.= (ff + (- ff)) + (- gg) by RLVECT_1:def 6
.= (0. (Polynom-Ring n,L)) + (- gg) by RLVECT_1:16
.= - gg by ALGSTR_1:def 5 ;
then - (- gg) in P -Ideal by A16, IDEAL_1:14;
then A17: g in P -Ideal by RLVECT_1:30;
assume not PolyRedRel P,T reduces f, 0_ n,L ; :: thesis: contradiction
then g <> 0_ n,L by A14, REWRITE1:def 6;
then g9 is_reducible_wrt P,T by A2, A17;
then consider u being Polynomial of n,L such that
A18: g9 reduces_to u,P,T by POLYRED:def 9;
A19: [g9,u] in PolyRedRel P,T by A18, POLYRED:def 13;
g is_a_normal_form_wrt PolyRedRel P,T by A14, REWRITE1:def 6;
hence contradiction by A19, REWRITE1:def 5; :: thesis: verum
end;
end;
end;
now
let a, b, c be set ; :: thesis: ( [a,b] in PolyRedRel P,T & [a,c] in PolyRedRel P,T implies b,c are_convergent_wrt PolyRedRel P,T )
assume that
A20: [a,b] in PolyRedRel P,T and
A21: [a,c] in PolyRedRel P,T ; :: thesis: b,c are_convergent_wrt PolyRedRel P,T
consider a9, b9 being set such that
a9 in NonZero (Polynom-Ring n,L) and
A22: b9 in the carrier of (Polynom-Ring n,L) and
A23: [a,b] = [a9,b9] by A20, ZFMISC_1:def 2;
A24: b9 = [a,b] `2 by A23, MCART_1:def 2
.= b by MCART_1:def 2 ;
a,b are_convertible_wrt PolyRedRel P,T by A20, REWRITE1:30;
then A25: b,a are_convertible_wrt PolyRedRel P,T by REWRITE1:32;
consider aa, c9 being set such that
aa in NonZero (Polynom-Ring n,L) and
A26: c9 in the carrier of (Polynom-Ring n,L) and
A27: [a,c] = [aa,c9] by A21, ZFMISC_1:def 2;
A28: c9 = [a,c] `2 by A27, MCART_1:def 2
.= c by MCART_1:def 2 ;
reconsider b9 = b9, c9 = c9 as Polynomial of n,L by A22, A26, POLYNOM1:def 27;
reconsider bb = b9, cc = c9 as Element of (Polynom-Ring n,L) by POLYNOM1:def 27;
reconsider bb = bb, cc = cc as Element of (Polynom-Ring n,L) ;
a,c are_convertible_wrt PolyRedRel P,T by A21, REWRITE1:30;
then bb,cc are_congruent_mod P -Ideal by A24, A28, A25, POLYRED:57, REWRITE1:31;
then A29: bb - cc in P -Ideal by POLYRED:def 14;
b9 - c9 = bb - cc by Lm2;
hence b,c are_convergent_wrt PolyRedRel P,T by A11, A24, A28, A29, POLYRED:50; :: thesis: verum
end;
hence PolyRedRel P,T is locally-confluent by REWRITE1:def 24; :: thesis: verum