TSTP Solution File: GRP032-3 by Twee---2.4.2

View Problem - Process Solution

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% File     : Twee---2.4.2
% Problem  : GRP032-3 : TPTP v8.1.2. Released v1.0.0.
% 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 : n018.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 01:16:42 EDT 2023

% Result   : Unsatisfiable 0.13s 0.39s
% Output   : Proof 0.13s
% Verified : 
% SZS Type : -

% Comments : 
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%----WARNING: Could not form TPTP format derivation
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%----ORIGINAL SYSTEM OUTPUT
% 0.06/0.12  % Problem  : GRP032-3 : TPTP v8.1.2. Released v1.0.0.
% 0.06/0.13  % 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 : n018.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 : Tue Aug 29 00:04:02 EDT 2023
% 0.13/0.34  % CPUTime  : 
% 0.13/0.39  Command-line arguments: --no-flatten-goal
% 0.13/0.39  
% 0.13/0.39  % SZS status Unsatisfiable
% 0.13/0.39  
% 0.13/0.39  % SZS output start Proof
% 0.13/0.39  Take the following subset of the input axioms:
% 0.13/0.39    fof(a_is_in_subgroup, hypothesis, subgroup_member(a)).
% 0.13/0.39    fof(closure_of_product_and_inverse, axiom, ![B, C, A2]: (~subgroup_member(A2) | (~subgroup_member(B) | (~product(A2, inverse(B), C) | subgroup_member(C))))).
% 0.13/0.39    fof(prove_identity_is_in_subgroup, negated_conjecture, ~subgroup_member(identity)).
% 0.13/0.39    fof(right_inverse, axiom, ![X]: product(X, inverse(X), identity)).
% 0.13/0.39  
% 0.13/0.39  Now clausify the problem and encode Horn clauses using encoding 3 of
% 0.13/0.39  http://www.cse.chalmers.se/~nicsma/papers/horn.pdf.
% 0.13/0.39  We repeatedly replace C & s=t => u=v by the two clauses:
% 0.13/0.39    fresh(y, y, x1...xn) = u
% 0.13/0.39    C => fresh(s, t, x1...xn) = v
% 0.13/0.39  where fresh is a fresh function symbol and x1..xn are the free
% 0.13/0.39  variables of u and v.
% 0.13/0.39  A predicate p(X) is encoded as p(X)=true (this is sound, because the
% 0.13/0.39  input problem has no model of domain size 1).
% 0.13/0.39  
% 0.13/0.39  The encoding turns the above axioms into the following unit equations and goals:
% 0.13/0.39  
% 0.13/0.39  Axiom 1 (a_is_in_subgroup): subgroup_member(a) = true.
% 0.13/0.39  Axiom 2 (closure_of_product_and_inverse): fresh3(X, X, Y) = true.
% 0.13/0.39  Axiom 3 (right_inverse): product(X, inverse(X), identity) = true.
% 0.13/0.39  Axiom 4 (closure_of_product_and_inverse): fresh7(X, X, Y, Z, W) = subgroup_member(W).
% 0.13/0.39  Axiom 5 (closure_of_product_and_inverse): fresh6(X, X, Y, Z, W) = fresh7(subgroup_member(Y), true, Y, Z, W).
% 0.13/0.39  Axiom 6 (closure_of_product_and_inverse): fresh6(subgroup_member(X), true, Y, X, Z) = fresh3(product(Y, inverse(X), Z), true, Z).
% 0.13/0.39  
% 0.13/0.39  Goal 1 (prove_identity_is_in_subgroup): subgroup_member(identity) = true.
% 0.13/0.39  Proof:
% 0.13/0.39    subgroup_member(identity)
% 0.13/0.39  = { by axiom 4 (closure_of_product_and_inverse) R->L }
% 0.13/0.39    fresh7(true, true, a, a, identity)
% 0.13/0.39  = { by axiom 1 (a_is_in_subgroup) R->L }
% 0.13/0.39    fresh7(subgroup_member(a), true, a, a, identity)
% 0.13/0.39  = { by axiom 5 (closure_of_product_and_inverse) R->L }
% 0.13/0.39    fresh6(true, true, a, a, identity)
% 0.13/0.39  = { by axiom 1 (a_is_in_subgroup) R->L }
% 0.13/0.39    fresh6(subgroup_member(a), true, a, a, identity)
% 0.13/0.39  = { by axiom 6 (closure_of_product_and_inverse) }
% 0.13/0.39    fresh3(product(a, inverse(a), identity), true, identity)
% 0.13/0.39  = { by axiom 3 (right_inverse) }
% 0.13/0.39    fresh3(true, true, identity)
% 0.13/0.39  = { by axiom 2 (closure_of_product_and_inverse) }
% 0.13/0.39    true
% 0.13/0.39  % SZS output end Proof
% 0.13/0.39  
% 0.13/0.39  RESULT: Unsatisfiable (the axioms are contradictory).
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