TSTP Solution File: LCL512+1 by Twee---2.4.2

View Problem - Process Solution

%------------------------------------------------------------------------------
% File     : Twee---2.4.2
% Problem  : LCL512+1 : TPTP v8.1.2. Released v3.3.0.
% Transfm  : none
% Format   : tptp:raw
% Command  : parallel-twee %s --tstp --conditional-encoding if --smaller --drop-non-horn --give-up-on-saturation --explain-encoding --formal-proof

% Computer : n032.cluster.edu
% Model    : x86_64 x86_64
% CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 2.10GHz
% Memory   : 8042.1875MB
% OS       : Linux 3.10.0-693.el7.x86_64
% CPULimit : 300s
% WCLimit  : 300s
% DateTime : Thu Aug 31 08:19:16 EDT 2023

% Result   : Theorem 0.13s 0.37s
% Output   : Proof 0.13s
% Verified : 
% SZS Type : -

% Comments : 
%------------------------------------------------------------------------------
%----WARNING: Could not form TPTP format derivation
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.00/0.09  % Problem  : LCL512+1 : TPTP v8.1.2. Released v3.3.0.
% 0.00/0.10  % Command  : parallel-twee %s --tstp --conditional-encoding if --smaller --drop-non-horn --give-up-on-saturation --explain-encoding --formal-proof
% 0.08/0.28  % Computer : n032.cluster.edu
% 0.08/0.28  % Model    : x86_64 x86_64
% 0.08/0.28  % CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.08/0.28  % Memory   : 8042.1875MB
% 0.08/0.28  % OS       : Linux 3.10.0-693.el7.x86_64
% 0.08/0.28  % CPULimit : 300
% 0.08/0.28  % WCLimit  : 300
% 0.08/0.28  % DateTime : Fri Aug 25 05:15:57 EDT 2023
% 0.08/0.28  % CPUTime  : 
% 0.13/0.37  Command-line arguments: --lhs-weight 1 --flip-ordering --normalise-queue-percent 10 --cp-renormalise-threshold 10
% 0.13/0.37  
% 0.13/0.37  % SZS status Theorem
% 0.13/0.37  
% 0.13/0.37  % SZS output start Proof
% 0.13/0.37  Take the following subset of the input axioms:
% 0.13/0.37    fof(equivalence_1, axiom, equivalence_1 <=> ![X, Y]: is_a_theorem(implies(equiv(X, Y), implies(X, Y)))).
% 0.13/0.37    fof(hilbert_equivalence_1, conjecture, equivalence_1).
% 0.13/0.37    fof(kn2, axiom, kn2 <=> ![P, Q]: is_a_theorem(implies(and(P, Q), P))).
% 0.13/0.37    fof(op_equiv, axiom, op_equiv => ![X2, Y2]: equiv(X2, Y2)=and(implies(X2, Y2), implies(Y2, X2))).
% 0.13/0.37    fof(rosser_kn2, axiom, kn2).
% 0.13/0.37    fof(rosser_op_equiv, axiom, op_equiv).
% 0.13/0.37  
% 0.13/0.37  Now clausify the problem and encode Horn clauses using encoding 3 of
% 0.13/0.37  http://www.cse.chalmers.se/~nicsma/papers/horn.pdf.
% 0.13/0.37  We repeatedly replace C & s=t => u=v by the two clauses:
% 0.13/0.37    fresh(y, y, x1...xn) = u
% 0.13/0.37    C => fresh(s, t, x1...xn) = v
% 0.13/0.37  where fresh is a fresh function symbol and x1..xn are the free
% 0.13/0.37  variables of u and v.
% 0.13/0.37  A predicate p(X) is encoded as p(X)=true (this is sound, because the
% 0.13/0.37  input problem has no model of domain size 1).
% 0.13/0.37  
% 0.13/0.37  The encoding turns the above axioms into the following unit equations and goals:
% 0.13/0.37  
% 0.13/0.37  Axiom 1 (rosser_kn2): kn2 = true.
% 0.13/0.37  Axiom 2 (rosser_op_equiv): op_equiv = true.
% 0.13/0.37  Axiom 3 (equivalence_1): fresh46(X, X) = true.
% 0.13/0.37  Axiom 4 (kn2_1): fresh31(X, X, Y, Z) = true.
% 0.13/0.37  Axiom 5 (op_equiv): fresh23(X, X, Y, Z) = equiv(Y, Z).
% 0.13/0.37  Axiom 6 (kn2_1): fresh31(kn2, true, X, Y) = is_a_theorem(implies(and(X, Y), X)).
% 0.13/0.37  Axiom 7 (op_equiv): fresh23(op_equiv, true, X, Y) = and(implies(X, Y), implies(Y, X)).
% 0.13/0.37  Axiom 8 (equivalence_1): fresh46(is_a_theorem(implies(equiv(x3, y3), implies(x3, y3))), true) = equivalence_1.
% 0.13/0.37  
% 0.13/0.37  Goal 1 (hilbert_equivalence_1): equivalence_1 = true.
% 0.13/0.37  Proof:
% 0.13/0.37    equivalence_1
% 0.13/0.37  = { by axiom 8 (equivalence_1) R->L }
% 0.13/0.37    fresh46(is_a_theorem(implies(equiv(x3, y3), implies(x3, y3))), true)
% 0.13/0.37  = { by axiom 5 (op_equiv) R->L }
% 0.13/0.37    fresh46(is_a_theorem(implies(fresh23(true, true, x3, y3), implies(x3, y3))), true)
% 0.13/0.37  = { by axiom 2 (rosser_op_equiv) R->L }
% 0.13/0.37    fresh46(is_a_theorem(implies(fresh23(op_equiv, true, x3, y3), implies(x3, y3))), true)
% 0.13/0.38  = { by axiom 7 (op_equiv) }
% 0.13/0.38    fresh46(is_a_theorem(implies(and(implies(x3, y3), implies(y3, x3)), implies(x3, y3))), true)
% 0.13/0.38  = { by axiom 6 (kn2_1) R->L }
% 0.13/0.38    fresh46(fresh31(kn2, true, implies(x3, y3), implies(y3, x3)), true)
% 0.13/0.38  = { by axiom 1 (rosser_kn2) }
% 0.13/0.38    fresh46(fresh31(true, true, implies(x3, y3), implies(y3, x3)), true)
% 0.13/0.38  = { by axiom 4 (kn2_1) }
% 0.13/0.38    fresh46(true, true)
% 0.13/0.38  = { by axiom 3 (equivalence_1) }
% 0.13/0.38    true
% 0.13/0.38  % SZS output end Proof
% 0.13/0.38  
% 0.13/0.38  RESULT: Theorem (the conjecture is true).
%------------------------------------------------------------------------------