TSTP Solution File: SET907+1 by Twee---2.4.2

View Problem - Process Solution

%------------------------------------------------------------------------------
% File     : Twee---2.4.2
% Problem  : SET907+1 : TPTP v8.1.2. Released v3.2.0.
% 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 : n022.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 15:33:41 EDT 2023

% Result   : Theorem 0.19s 0.40s
% Output   : Proof 0.19s
% Verified : 
% SZS Type : -

% Comments : 
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%----WARNING: Could not form TPTP format derivation
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%----ORIGINAL SYSTEM OUTPUT
% 0.00/0.12  % Problem  : SET907+1 : TPTP v8.1.2. Released v3.2.0.
% 0.00/0.13  % Command  : parallel-twee %s --tstp --conditional-encoding if --smaller --drop-non-horn --give-up-on-saturation --explain-encoding --formal-proof
% 0.13/0.34  % Computer : n022.cluster.edu
% 0.13/0.34  % Model    : x86_64 x86_64
% 0.13/0.34  % CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.13/0.34  % Memory   : 8042.1875MB
% 0.13/0.34  % OS       : Linux 3.10.0-693.el7.x86_64
% 0.13/0.34  % CPULimit : 300
% 0.13/0.34  % WCLimit  : 300
% 0.13/0.34  % DateTime : Sat Aug 26 09:19:25 EDT 2023
% 0.13/0.34  % CPUTime  : 
% 0.19/0.40  Command-line arguments: --set-join --lhs-weight 1 --no-flatten-goal --complete-subsets --goal-heuristic
% 0.19/0.40  
% 0.19/0.40  % SZS status Theorem
% 0.19/0.40  
% 0.19/0.40  % SZS output start Proof
% 0.19/0.40  Take the following subset of the input axioms:
% 0.19/0.40    fof(commutativity_k2_tarski, axiom, ![A, B]: unordered_pair(A, B)=unordered_pair(B, A)).
% 0.19/0.40    fof(t12_xboole_1, axiom, ![A2, B2]: (subset(A2, B2) => set_union2(A2, B2)=B2)).
% 0.19/0.40    fof(t38_zfmisc_1, axiom, ![C, B2, A2_2]: (subset(unordered_pair(A2_2, B2), C) <=> (in(A2_2, C) & in(B2, C)))).
% 0.19/0.40    fof(t48_zfmisc_1, conjecture, ![A3, B2, C2]: ((in(A3, B2) & in(C2, B2)) => set_union2(unordered_pair(A3, C2), B2)=B2)).
% 0.19/0.40  
% 0.19/0.40  Now clausify the problem and encode Horn clauses using encoding 3 of
% 0.19/0.40  http://www.cse.chalmers.se/~nicsma/papers/horn.pdf.
% 0.19/0.40  We repeatedly replace C & s=t => u=v by the two clauses:
% 0.19/0.40    fresh(y, y, x1...xn) = u
% 0.19/0.40    C => fresh(s, t, x1...xn) = v
% 0.19/0.40  where fresh is a fresh function symbol and x1..xn are the free
% 0.19/0.40  variables of u and v.
% 0.19/0.40  A predicate p(X) is encoded as p(X)=true (this is sound, because the
% 0.19/0.40  input problem has no model of domain size 1).
% 0.19/0.40  
% 0.19/0.40  The encoding turns the above axioms into the following unit equations and goals:
% 0.19/0.40  
% 0.19/0.40  Axiom 1 (commutativity_k2_tarski): unordered_pair(X, Y) = unordered_pair(Y, X).
% 0.19/0.40  Axiom 2 (t48_zfmisc_1): in(c, b) = true2.
% 0.19/0.40  Axiom 3 (t48_zfmisc_1_1): in(a, b) = true2.
% 0.19/0.40  Axiom 4 (t12_xboole_1): fresh(X, X, Y, Z) = Z.
% 0.19/0.40  Axiom 5 (t38_zfmisc_1): fresh5(X, X, Y, Z, W) = subset(unordered_pair(Y, Z), W).
% 0.19/0.40  Axiom 6 (t38_zfmisc_1): fresh4(X, X, Y, Z, W) = true2.
% 0.19/0.40  Axiom 7 (t12_xboole_1): fresh(subset(X, Y), true2, X, Y) = set_union2(X, Y).
% 0.19/0.40  Axiom 8 (t38_zfmisc_1): fresh5(in(X, Y), true2, Z, X, Y) = fresh4(in(Z, Y), true2, Z, X, Y).
% 0.19/0.40  
% 0.19/0.40  Goal 1 (t48_zfmisc_1_2): set_union2(unordered_pair(a, c), b) = b.
% 0.19/0.40  Proof:
% 0.19/0.40    set_union2(unordered_pair(a, c), b)
% 0.19/0.40  = { by axiom 1 (commutativity_k2_tarski) }
% 0.19/0.40    set_union2(unordered_pair(c, a), b)
% 0.19/0.40  = { by axiom 7 (t12_xboole_1) R->L }
% 0.19/0.40    fresh(subset(unordered_pair(c, a), b), true2, unordered_pair(c, a), b)
% 0.19/0.40  = { by axiom 5 (t38_zfmisc_1) R->L }
% 0.19/0.40    fresh(fresh5(true2, true2, c, a, b), true2, unordered_pair(c, a), b)
% 0.19/0.40  = { by axiom 3 (t48_zfmisc_1_1) R->L }
% 0.19/0.40    fresh(fresh5(in(a, b), true2, c, a, b), true2, unordered_pair(c, a), b)
% 0.19/0.40  = { by axiom 8 (t38_zfmisc_1) }
% 0.19/0.40    fresh(fresh4(in(c, b), true2, c, a, b), true2, unordered_pair(c, a), b)
% 0.19/0.40  = { by axiom 2 (t48_zfmisc_1) }
% 0.19/0.40    fresh(fresh4(true2, true2, c, a, b), true2, unordered_pair(c, a), b)
% 0.19/0.40  = { by axiom 6 (t38_zfmisc_1) }
% 0.19/0.40    fresh(true2, true2, unordered_pair(c, a), b)
% 0.19/0.40  = { by axiom 4 (t12_xboole_1) }
% 0.19/0.40    b
% 0.19/0.40  % SZS output end Proof
% 0.19/0.40  
% 0.19/0.40  RESULT: Theorem (the conjecture is true).
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