%--------------------------------------------------------------------------
% File     : MSC007-1.005 : TPTP v9.0.0. Bugfixed v2.1.0.
% Domain   : Miscellaneous
% Problem  : Cook pigeon-hole problem
% Version  : [Pel86] axioms : Especial.
%            Theorem formulation : Propositional.
% English  : Suppose there are N holes and N+1 pigeons to put in the
%            holes. Every pigeon is in a hole and no hole contains more
%            than one pigeon. Prove that this is impossible. The size is
%            the number of pigeons.

% Refs     : [CR79]  Cook & Reckhow (1979), The Relative Efficiency of Prop
%          : [Pel86] Pelletier (1986), Seventy-five Problems for Testing Au
% Source   : [Pel86]
% Names    : Pelletier 72 (Size 4) [Pel86]
%          : pigeon.in (Size 4) [OTTER]

% Status   : Unsatisfiable
% Rating   : 0.00 v2.0.0
% Syntax   :

% Comments : For an N hole problem, the number of propositions is N^2 + N
%            and the number of clauses is (N^3 + N^2)/2 + N+1. Thus the
%            number of propositions increases quadratically and the number
%            of clauses increases cubically.
%          : tptp2X: -ftptp -s5 MSC007-1.g
% Bugfixes : v2.1.0 - Replaced by a new SOTA size.
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