twee-2.4: tests/GRP196-1.p
%--------------------------------------------------------------------------
% File : GRP196-1 : TPTP v7.4.0. Released v2.2.0.
% Domain : Group Theory (Semigroups)
% Problem : In semigroups, xyyy=yyyx -> (uy)^9 = u^9v^9.
% Version : [MP96] (equality) axioms.
% English :
% Refs : [McC98] McCune (1998), Email to G. Sutcliffe
% : [MP96] McCune & Padmanabhan (1996), Automated Deduction in Eq
% : [McC95] McCune (1995), Four Challenge Problems in Equational L
% Source : [McC98]
% Names : CS-3 [MP96]
% : Problem B [McC95]
% Status : Unsatisfiable
% Rating : 0.88 v7.4.0, 0.91 v7.3.0, 0.89 v7.0.0, 0.95 v6.4.0, 1.00 v4.0.1, 0.93 v4.0.0, 0.92 v3.7.0, 0.89 v3.4.0, 1.00 v3.3.0, 0.93 v3.1.0, 1.00 v2.2.1
% Syntax : Number of clauses : 3 ( 0 non-Horn; 3 unit; 1 RR)
% Number of atoms : 3 ( 3 equality)
% Maximal clause size : 1 ( 1 average)
% Number of predicates : 1 ( 0 propositional; 2-2 arity)
% Number of functors : 3 ( 2 constant; 0-2 arity)
% Number of variables : 5 ( 0 singleton)
% Maximal term depth : 18 ( 8 average)
% SPC : CNF_UNS_RFO_PEQ_UEQ
% Comments : The problem was originally posed for cancellative semigroups,
% Otter does this with a nonstandard representation [MP96].
%--------------------------------------------------------------------------
%----Include semigroups axioms
include('Axioms/GRP008-0.ax').
%--------------------------------------------------------------------------
%----Hypothesis:
cnf(condition,hypothesis,
( '*'(X,'*'(Y,'*'(Y,Y))) = '*'(Y,'*'(Y,'*'(Y,X))) )).
%----Denial of conclusion:
cnf(prove_this,negated_conjecture,
( '*'(a,'*'(b,'*'(a,'*'(b,'*'(a,'*'(b,'*'(a,'*'(b,'*'(a,'*'(b,'*'(a,'*'(b,'*'(a,'*'(b,'*'(a,'*'(b,'*'(a,b))))))))))))))))) != '*'(a,'*'(a,'*'(a,'*'(a,'*'(a,'*'(a,'*'(a,'*'(a,'*'(a,'*'(b,'*'(b,'*'(b,'*'(b,'*'(b,'*'(b,'*'(b,'*'(b,b))))))))))))))))) )).
%--------------------------------------------------------------------------