## TPTP Problem File: SEV309^5.p

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```%------------------------------------------------------------------------------
% File     : SEV309^5 : TPTP v7.5.0. Released v4.0.0.
% Domain   : Set Theory
% Problem  : TPS problem THM1
% Version  : Especial.
% English  : Related to the Knaster-Tarski theorem.

% Refs     : [Bro09] Brown (2009), Email to Geoff Sutcliffe
% Source   : [Bro09]
% Names    : tps_0510 [Bro09]
%          : THM1 [TPS]

% Status   : Theorem
% Rating   : 1.00 v6.2.0, 0.86 v5.5.0, 0.83 v5.4.0, 0.80 v5.3.0, 1.00 v4.0.0
% Syntax   : Number of formulae    :    1 (   0 unit;   0 type;   0 defn)
%            Number of atoms       :   21 (   2 equality;  19 variable)
%            Maximal formula depth :   12 (  12 average)
%            Number of connectives :   17 (   1   ~;   1   |;   1   &;   9   @)
%                                         (   1 <=>;   4  =>;   0  <=;   0 <~>)
%                                         (   0  ~|;   0  ~&)
%            Number of type conns  :    8 (   8   >;   0   *;   0   +;   0  <<)
%            Number of symbols     :    2 (   0   :;   0   =)
%            Number of variables   :    9 (   0 sgn;   5   !;   4   ?;   0   ^)
%                                         (   9   :;   0  !>;   0  ?*)
%                                         (   0  @-;   0  @+)
% SPC      : TH0_THM_EQU_NAR

% Comments : This problem is from the TPS library. Copyright (c) 2009 The TPS
%            project in the Department of Mathematical Sciences at Carnegie
%          : Polymorphic definitions expanded.
%------------------------------------------------------------------------------
thf(cTHM1_pme,conjecture,
( ! [P: \$i > \$o,Q: \$i > \$o] :
? [X: \$i] :
( ( ( P @ X )
<=> ( Q @ X ) )
=> ( P = Q ) )
=> ! [K: ( \$i > \$o ) > \$i > \$o] :
( ? [X: \$i > \$o,Y: \$i > \$o] :
( ! [Xx: \$i] :
( ( X @ Xx )
=> ( Y @ Xx ) )
& ~ ( ! [Xx: \$i] :
( ( K @ X @ Xx )
=> ( K @ Y @ Xx ) ) ) )
| ? [U: \$i > \$o] :
( ( K @ U )
= U ) ) )).

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