============================== Prover9 ===============================
Prover9 (32) version 2009-11A, November 2009.
Process 4311 was started by mccune on cleo,
Tue Nov  3 09:38:21 2009
The command was "/home/mccune/LADR/bin/prover9 -f qg1.in".
============================== end of head ===========================

============================== INPUT =================================

% Reading from file qg1.in

assign(max_seconds,30).

formulas(sos).
x * (x \ y) = y.
x \ (x * y) = y.
(x / y) * y = x.
(x * y) / y = x.
x * (y * (y * x)) = y * x.
end_of_list.

formulas(goals).
y * (y * x) = x * y.
end_of_list.

============================== end of input ==========================

============================== PROCESS NON-CLAUSAL FORMULAS ==========

% Formulas that are not ordinary clauses:
1 y * (y * x) = x * y # label(non_clause) # label(goal).  [goal].

============================== end of process non-clausal formulas ===

============================== PROCESS INITIAL CLAUSES ===============

% Clauses before input processing:

formulas(usable).
end_of_list.

formulas(sos).
x * (x \ y) = y.  [assumption].
x \ (x * y) = y.  [assumption].
(x / y) * y = x.  [assumption].
(x * y) / y = x.  [assumption].
x * (y * (y * x)) = y * x.  [assumption].
c1 * (c1 * c2) != c2 * c1.  [deny(1)].
end_of_list.

formulas(demodulators).
end_of_list.

============================== PREDICATE ELIMINATION =================

No predicates eliminated.

============================== end predicate elimination =============

Auto_denials:  (no changes).

Term ordering decisions:
Predicate symbol precedence:  predicate_order([ = ]).
Function symbol precedence:  function_order([ c1, c2, *, /, \ ]).
After inverse_order:  (no changes).
Unfolding symbols: (none).

Auto_inference settings:
  % set(paramodulation).  % (positive equality literals)

Auto_process settings:  (no changes).

kept:      2 x * (x \ y) = y.  [assumption].
kept:      3 x \ (x * y) = y.  [assumption].
kept:      4 (x / y) * y = x.  [assumption].
kept:      5 (x * y) / y = x.  [assumption].
kept:      6 x * (y * (y * x)) = y * x.  [assumption].
           7 c1 * (c1 * c2) != c2 * c1.  [deny(1)].
kept:      8 c2 * c1 != c1 * (c1 * c2).  [copy(7),flip(a)].

============================== end of process initial clauses ========

============================== CLAUSES FOR SEARCH ====================

% Clauses after input processing:

formulas(usable).
end_of_list.

formulas(sos).
2 x * (x \ y) = y.  [assumption].
3 x \ (x * y) = y.  [assumption].
4 (x / y) * y = x.  [assumption].
5 (x * y) / y = x.  [assumption].
6 x * (y * (y * x)) = y * x.  [assumption].
8 c2 * c1 != c1 * (c1 * c2).  [copy(7),flip(a)].
end_of_list.

formulas(demodulators).
2 x * (x \ y) = y.  [assumption].
3 x \ (x * y) = y.  [assumption].
4 (x / y) * y = x.  [assumption].
5 (x * y) / y = x.  [assumption].
6 x * (y * (y * x)) = y * x.  [assumption].
end_of_list.

============================== end of clauses for search =============

============================== SEARCH ================================

% Starting search at 0.01 seconds.

given #1 (I,wt=7): 2 x * (x \ y) = y.  [assumption].

given #2 (I,wt=7): 3 x \ (x * y) = y.  [assumption].

given #3 (I,wt=7): 4 (x / y) * y = x.  [assumption].

given #4 (I,wt=7): 5 (x * y) / y = x.  [assumption].

given #5 (I,wt=11): 6 x * (y * (y * x)) = y * x.  [assumption].

given #6 (I,wt=9): 8 c2 * c1 != c1 * (c1 * c2).  [copy(7),flip(a)].

given #7 (A,wt=7): 9 (x / y) \ x = y.  [para(4(a,1),3(a,1,2))].

given #8 (T,wt=7): 10 x / (y \ x) = y.  [para(2(a,1),5(a,1,1))].

given #9 (T,wt=9): 11 (x \ y) * (x * y) = y.  [para(2(a,1),6(a,1,2,2)),rewrite([2(5)])].

given #10 (T,wt=9): 13 x * ((y / x) * y) = y.  [para(4(a,1),6(a,1,2,2)),rewrite([4(5)])].

given #11 (T,wt=5): 27 x * x = x.  [para(4(a,1),13(a,1,2))].

given #12 (A,wt=11): 14 (x * y) / (x * (x * y)) = y.  [para(6(a,1),5(a,1,1))].

given #13 (T,wt=5): 29 x / x = x.  [para(27(a,1),5(a,1,1))].

given #14 (T,wt=9): 31 (x / (x / y)) * x = y.  [back_rewrite(25),rewrite([30(3)])].

given #15 (T,wt=9): 32 x \ y = (y / x) * y.  [back_rewrite(20),rewrite([30(3)])].

given #16 (T,wt=9): 34 x / (x / y) = y / x.  [para(31(a,1),5(a,1,1)),flip(a)].

given #17 (A,wt=15): 15 (x * (x * y)) * (y * (x * y)) = x * y.  [para(6(a,1),6(a,1,2,2)),rewrite([6(8)])].

given #18 (T,wt=9): 36 (x / y) * (y / x) = y.  [para(34(a,1),4(a,1,1))].

given #19 (T,wt=11): 28 ((x / y) * x) * (y * x) = x.  [para(13(a,1),6(a,1,2,2)),rewrite([13(7)])].

given #20 (T,wt=11): 30 x / (y * x) = (x / y) * x.  [para(13(a,1),14(a,1,1)),rewrite([13(3)])].

given #21 (T,wt=11): 35 x * ((x / (x / y)) * y) = y.  [para(31(a,1),6(a,1,2,2)),rewrite([31(7)])].

given #22 (A,wt=11): 37 (x * y) / x = (y / x) * y.  [para(5(a,1),34(a,1,2)),rewrite([30(4)])].

given #23 (T,wt=11): 38 (x / (y / x)) * x = x / y.  [para(34(a,1),31(a,1,1,2))].

given #24 (T,wt=11): 42 (x / y) / x = x / (y / x).  [para(34(a,1),34(a,1,2)),flip(a)].

given #25 (T,wt=11): 44 x / (y / (y / x)) = y / x.  [para(34(a,2),34(a,1,2))].

given #26 (T,wt=11): 49 ((x / y) * x) * y = y * x.  [para(5(a,1),36(a,1,2)),rewrite([30(2)])].

============================== PROOF =================================

% Proof 1 at 0.02 (+ 0.00) seconds.
% Length of proof is 27.
% Level of proof is 12.
% Maximum clause weight is 15.000.
% Given clauses 26.

1 y * (y * x) = x * y # label(non_clause) # label(goal).  [goal].
2 x * (x \ y) = y.  [assumption].
3 x \ (x * y) = y.  [assumption].
4 (x / y) * y = x.  [assumption].
5 (x * y) / y = x.  [assumption].
6 x * (y * (y * x)) = y * x.  [assumption].
7 c1 * (c1 * c2) != c2 * c1.  [deny(1)].
8 c2 * c1 != c1 * (c1 * c2).  [copy(7),flip(a)].
9 (x / y) \ x = y.  [para(4(a,1),3(a,1,2))].
11 (x \ y) * (x * y) = y.  [para(2(a,1),6(a,1,2,2)),rewrite([2(5)])].
13 x * ((y / x) * y) = y.  [para(4(a,1),6(a,1,2,2)),rewrite([4(5)])].
14 (x * y) / (x * (x * y)) = y.  [para(6(a,1),5(a,1,1))].
15 (x * (x * y)) * (y * (x * y)) = x * y.  [para(6(a,1),6(a,1,2,2)),rewrite([6(8)])].
20 x \ y = y / (x * y).  [para(11(a,1),5(a,1,1)),flip(a)].
25 x / ((x / y) * x) = y.  [back_rewrite(9),rewrite([20(2)])].
28 ((x / y) * x) * (y * x) = x.  [para(13(a,1),6(a,1,2,2)),rewrite([13(7)])].
30 x / (y * x) = (x / y) * x.  [para(13(a,1),14(a,1,1)),rewrite([13(3)])].
31 (x / (x / y)) * x = y.  [back_rewrite(25),rewrite([30(3)])].
34 x / (x / y) = y / x.  [para(31(a,1),5(a,1,1)),flip(a)].
36 (x / y) * (y / x) = y.  [para(34(a,1),4(a,1,1))].
37 (x * y) / x = (y / x) * y.  [para(5(a,1),34(a,1,2)),rewrite([30(4)])].
49 ((x / y) * x) * y = y * x.  [para(5(a,1),36(a,1,2)),rewrite([30(2)])].
87 (x / y) * x = y * (x / y).  [para(31(a,1),49(a,1,1)),flip(a)].
91 (x * (y / x)) * x = x * y.  [para(49(a,1),15(a,2)),rewrite([87(2),87(4),87(8),15(11)])].
93 (x * (y / x)) * (x * y) = y.  [para(28(a,1),49(a,2)),rewrite([87(3),87(6),87(9),91(10)])].
97 x * (x * y) = y * x.  [para(37(a,1),49(a,1,1,1)),rewrite([87(2),93(4)]),flip(a)].
98 $F.  [resolve(97,a,8,a(flip))].

============================== end of proof ==========================

============================== STATISTICS ============================

Given=26. Generated=409. Kept=95. proofs=1.
Usable=20. Sos=34. Demods=59. Limbo=11, Disabled=35. Hints=0.
Kept_by_rule=0, Deleted_by_rule=0.
Forward_subsumed=314. Back_subsumed=1.
Sos_limit_deleted=0. Sos_displaced=0. Sos_removed=0.
New_demodulators=88 (0 lex), Back_demodulated=28. Back_unit_deleted=0.
Demod_attempts=3249. Demod_rewrites=718.
Res_instance_prunes=0. Para_instance_prunes=0. Basic_paramod_prunes=0.
Nonunit_fsub_feature_tests=0. Nonunit_bsub_feature_tests=0.
Megabytes=0.11.
User_CPU=0.02, System_CPU=0.00, Wall_clock=0.

============================== end of statistics =====================

============================== end of search =========================

THEOREM PROVED

Exiting with 1 proof.

Process 4311 exit (max_proofs) Tue Nov  3 09:38:21 2009
