1%--------------------------------------------------------------------------
2% File     : BOO003-4 : TPTP v5.5.0. Released v1.1.0.
3% Domain   : Boolean Algebra
4% Problem  : Multiplication is idempotent (X * X = X)
5% Version  : [Ver94] (equality) axioms.
6% English  :
7
8% Refs     : [Ver94] Veroff (1994), Problem Set
9% Source   : [Ver94]
10% Names    : TA [Ver94]
11
12% Status   : Unsatisfiable
13% Rating   : 0.10 v5.5.0, 0.05 v5.4.0, 0.00 v2.1.0, 0.13 v2.0.0
14% Syntax   : Number of clauses     :    9 (   0 non-Horn;   9 unit;   1 RR)
15%            Number of atoms       :    9 (   9 equality)
16%            Maximal clause size   :    1 (   1 average)
17%            Number of predicates  :    1 (   0 propositional; 2-2 arity)
18%            Number of functors    :    6 (   3 constant; 0-2 arity)
19%            Number of variables   :   14 (   0 singleton)
20%            Maximal term depth    :    3 (   2 average)
21% SPC      : CNF_UNS_RFO_PEQ_UEQ
22
23% Comments :
24%--------------------------------------------------------------------------
25%----Include boolean algebra axioms for equality formulation
26include('Axioms/BOO004-0.ax').
27%--------------------------------------------------------------------------
28cnf(prove_a_times_a_is_a,negated_conjecture,
29    (  multiply(a,a) != a )).
30
31%--------------------------------------------------------------------------
32