## TPTP Problem File: PUZ121^5.p

View Solutions - Solve Problem

```%------------------------------------------------------------------------------
% File     : PUZ121^5 : TPTP v7.0.0. Bugfixed v6.2.0.
% Domain   : Puzzles
% Problem  : TPS problem from CHECKERBOARD-THMS
% Version  : Especial.
% English  :

% Refs     : [Bro09] Brown (2009), Email to Geoff Sutcliffe
% Source   : [Bro09]
% Names    : tps_0815 [Bro09]

% Status   : CounterSatisfiable
% Rating   : 0.33 v6.2.0
% Syntax   : Number of formulae    :    9 (   0 unit;   5 type;   3 defn)
%            Number of atoms       :   84 (  11 equality;  20 variable)
%            Maximal formula depth :   14 (   7 average)
%            Number of connectives :   58 (   0   ~;   7   |;   4   &;  46   @)
%                                         (   0 <=>;   1  =>;   0  <=;   0 <~>)
%                                         (   0  ~|;   0  ~&)
%            Number of type conns  :    5 (   5   >;   0   *;   0   +;   0  <<)
%            Number of symbols     :    7 (   5   :;   0   =)
%            Number of variables   :    6 (   0 sgn;   2   !;   0   ?;   4   ^)
%                                         (   6   :;   0  !>;   0  ?*)
%                                         (   0  @-;   0  @+)
% SPC      : TH0_CSA_EQU_NAR

% Comments : This problem is from the TPS library. Copyright (c) 2009 The TPS
%            project in the Department of Mathematical Sciences at Carnegie
% Bugfixes : v5.2.0 - Added missing type declarations.
%          : v6.2.0 - Reordered definitions.
%------------------------------------------------------------------------------
thf(c1_type,type,(
c1: \$i )).

thf(s_type,type,(
s: \$i > \$i )).

thf(cCKB_BLACK_type,type,(
cCKB_BLACK: \$i > \$i > \$o )).

thf(cCKB_EVEN_type,type,(
cCKB_EVEN: \$i > \$o )).

thf(cCKB_ODD_type,type,(
cCKB_ODD: \$i > \$o )).

thf(cCKB_EVEN_def,definition,
( cCKB_EVEN
= ( ^ [Xx: \$i] :
( ( Xx
= ( s @ c1 ) )
| ( Xx
= ( s @ ( s @ ( s @ c1 ) ) ) )
| ( Xx
= ( s @ ( s @ ( s @ ( s @ ( s @ c1 ) ) ) ) ) )
| ( Xx
= ( s @ ( s @ ( s @ ( s @ ( s @ ( s @ ( s @ c1 ) ) ) ) ) ) ) ) ) ) )).

thf(cCKB_ODD_def,definition,
( cCKB_ODD
= ( ^ [Xx: \$i] :
( ( Xx = c1 )
| ( Xx
= ( s @ ( s @ c1 ) ) )
| ( Xx
= ( s @ ( s @ ( s @ ( s @ c1 ) ) ) ) )
| ( Xx
= ( s @ ( s @ ( s @ ( s @ ( s @ ( s @ c1 ) ) ) ) ) ) ) ) ) )).

thf(cCKB_BLACK_def,definition,
( cCKB_BLACK
= ( ^ [Xu: \$i,Xv: \$i] :
( ( ( cCKB_ODD @ Xu )
& ( cCKB_ODD @ Xv ) )
| ( ( cCKB_EVEN @ Xu )
& ( cCKB_EVEN @ Xv ) ) ) ) )).

thf(cCKB_L11000,conjecture,(
! [Xu: \$i,Xv: \$i] :
( ( cCKB_BLACK @ Xu @ Xv )
=> ( ( cCKB_BLACK @ ( s @ Xu ) @ ( s @ Xv ) )
& ( cCKB_BLACK @ Xu @ ( s @ ( s @ Xv ) ) )
& ( cCKB_BLACK @ ( s @ ( s @ Xu ) ) @ Xv ) ) ) )).

%------------------------------------------------------------------------------
```