%------------------------------------------------------------------------------
% File : Prover9---2026-6A
% Problem : ROB013-1 : TPTP v9.3.1. Released v1.0.0.
% Transfm : none
% Format : tptp:raw
% Command : prover9 -casc 300 -f /export/starexec/sandbox/benchmark/theBenchmark.p
% Computer : n016.cluster.edu
% Model : x86_64 x86_64
% CPU : Intel(R) Xeon(R) CPU E5-2620 v4 2.10GHz
% Memory : 8046.5625MB
% OS : Linux 6.8.0-71-generic
% CPULimit : 300s
% WCLimit : 300s
% DateTime : Sun Sep 27 08:26:57 AM UTC 2026
% Result : Unsatisfiable 0.17s 5.42s
% Output : CNFRefutation 0.17s
% Verified :
% SZS Type : Refutation
% Derivation depth : 6
% Number of leaves : 4
% Syntax : Number of formulae : 13 ( 13 unt; 0 def)
% Number of atoms : 13 ( 12 equ)
% Maximal formula atoms : 1 ( 1 avg)
% Number of connectives : 5 ( 5 ~; 0 |; 0 &)
% ( 0 <=>; 0 =>; 0 <=; 0 <~>)
% Maximal formula depth : 3 ( 2 avg)
% Maximal term depth : 6 ( 2 avg)
% Number of predicates : 2 ( 0 usr; 1 prp; 0-2 aty)
% Number of functors : 5 ( 5 usr; 3 con; 0-2 aty)
% Number of variables : 8 ( 0 sgn 4 !; 0 ?)
% Comments :
%------------------------------------------------------------------------------
fof(commutativity_of_add,axiom,
! [VAR_0,VAR_1] : add(VAR_0,VAR_1) = add(VAR_1,VAR_0),
file('theBenchmark.p',commutativity_of_add) ).
cnf(c_1,plain,
add(A,B) = add(B,A),
inference(clausify,[status(thm)],[commutativity_of_add]) ).
fof(robbins_axiom,axiom,
! [VAR_0,VAR_1] : negate(add(negate(add(VAR_0,VAR_1)),negate(add(VAR_0,negate(VAR_1))))) = VAR_0,
file('theBenchmark.p',robbins_axiom) ).
cnf(c_3,plain,
negate(add(negate(add(A,B)),negate(add(A,negate(B))))) = A,
inference(clausify,[status(thm)],[robbins_axiom]) ).
fof(condition,axiom,
negate(add(a,b)) = c,
file('theBenchmark.p',condition) ).
cnf(c_4,plain,
negate(add(a,b)) = c,
inference(clausify,[status(thm)],[condition]) ).
cnf(c_5,plain,
c = negate(add(a,b)),
inference(copy,[status(thm)],[c_4]) ).
fof(prove_result,axiom,
negate(add(c,negate(add(negate(b),a)))) != a,
file('theBenchmark.p',prove_result) ).
cnf(c_6,plain,
negate(add(c,negate(add(negate(b),a)))) != a,
inference(clausify,[status(thm)],[prove_result]) ).
cnf(c_8,plain,
negate(add(negate(add(a,b)),negate(add(negate(b),a)))) != a,
inference(paramod,[status(thm)],[c_5,c_6]) ).
cnf(c_9,plain,
negate(add(negate(add(a,b)),negate(add(a,negate(b))))) != a,
inference(paramod,[status(thm)],[c_1,c_8]) ).
cnf(c_10,plain,
a != a,
inference(paramod,[status(thm)],[c_3,c_9]) ).
cnf(c_7,plain,
$false,
inference(copy,[status(thm)],[c_10]) ).
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.00/0.03 % Problem : ROB013-1 : TPTP v9.3.1. Released v1.0.0.
% 0.00/0.04 % Command : prover9 -casc 300 -f /export/starexec/sandbox/benchmark/theBenchmark.p
% 0.13/5.39 % Computer : n016.cluster.edu
% 0.13/5.39 % Model : x86_64 x86_64
% 0.13/5.39 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.13/5.39 % Memory : 8046.5625MB
% 0.13/5.39 % OS : Linux 6.8.0-71-generic
% 0.13/5.39 % CPULimit : 300
% 0.13/5.39 % WCLimit : 300
% 0.13/5.39 % DateTime : Sat Sep 26 06:19:36 UTC 2026
% 0.17/5.40 % CPUTime :
% 0.17/5.40 % Prover9 (64) version 2026-6A, July 2026, CASC-J13.
% 0.17/5.40 % Process 180830 was started by sandbox on n016,
% 0.17/5.40 % Sat Sep 26 06:19:36 2026
% 0.17/5.40 % The command was "/export/starexec/sandbox/solver/bin/prover9 -casc 300 -f /export/starexec/sandbox/benchmark/theBenchmark.p".
% 0.17/5.41
% 0.17/5.41 % From the command line: assign(max_seconds, 300).
% 0.17/5.42
% 0.17/5.42 % SZS status Unsatisfiable for theBenchmark
% 0.17/5.42
% 0.17/5.42 % Proof 1 at 0.00 (+ 0.00) seconds.
% 0.17/5.42 % Length of proof is 6.
% 0.17/5.42 % Level of proof is 2.
% 0.17/5.42 % Maximum clause weight is 13.000.
% 0.17/5.42 % Given clauses 0.
% 0.17/5.42
% 0.17/5.42 % SZS output start CNFRefutation for theBenchmark
% See solution above
%------------------------------------------------------------------------------