0.00/0.10 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.09/0.10 % Command : twee %s --tstp --casc --quiet --explain-encoding --conditional-encoding if --smaller --drop-non-horn 0.09/0.30 % Computer : n015.cluster.edu 0.09/0.30 % Model : x86_64 x86_64 0.09/0.30 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz 0.09/0.30 % Memory : 8042.1875MB 0.09/0.30 % OS : Linux 3.10.0-693.el7.x86_64 0.09/0.30 % CPULimit : 960 0.09/0.30 % WCLimit : 120 0.09/0.30 % DateTime : Thu Jul 2 06:41:30 EDT 2020 0.09/0.30 % CPUTime : 0.13/0.58 % SZS status Theorem 0.13/0.58 0.13/0.58 % SZS output start Proof 0.13/0.58 Take the following subset of the input axioms: 0.13/0.58 fof(mighta, axiom, ![S1, S2]: (?[Ax, C]: (status(Ax, C, S1) & status(Ax, C, S2)) <=> mighta(S1, S2))). 0.13/0.58 fof(mighta_tac_thm, conjecture, mighta(tac, thm)). 0.13/0.58 fof(non_thm_spt, axiom, ?[Ax, C, I1]: (model(I1, Ax) & (?[I2]: model(I2, C) & ~model(I1, C)))). 0.13/0.58 fof(tac, axiom, ![Ax, C]: ((![I2]: model(I2, C) & ?[I1]: model(I1, Ax)) <=> status(Ax, C, tac))). 0.13/0.58 fof(tautology, axiom, ?[F]: ![I]: model(I, F)). 0.13/0.58 fof(thm, axiom, ![Ax, C]: (status(Ax, C, thm) <=> ![I1]: (model(I1, C) <= model(I1, Ax)))). 0.13/0.58 0.13/0.58 Now clausify the problem and encode Horn clauses using encoding 3 of 0.13/0.58 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 0.13/0.58 We repeatedly replace C & s=t => u=v by the two clauses: 0.13/0.58 fresh(y, y, x1...xn) = u 0.13/0.58 C => fresh(s, t, x1...xn) = v 0.13/0.58 where fresh is a fresh function symbol and x1..xn are the free 0.13/0.58 variables of u and v. 0.13/0.58 A predicate p(X) is encoded as p(X)=true (this is sound, because the 0.13/0.58 input problem has no model of domain size 1). 0.13/0.58 0.13/0.58 The encoding turns the above axioms into the following unit equations and goals: 0.13/0.58 0.13/0.58 Axiom 1 (mighta): fresh48(X, X, Y, Z, W, V) = mighta(Y, Z). 0.13/0.58 Axiom 2 (mighta): fresh47(X, X, Y, Z) = true2. 0.13/0.58 Axiom 3 (tac): fresh30(X, X, Y, Z, W) = status(Y, Z, tac). 0.13/0.59 Axiom 4 (tac): fresh29(X, X, Y, Z) = true2. 0.13/0.59 Axiom 5 (thm_2): fresh19(X, X, Y, Z) = true2. 0.13/0.59 Axiom 6 (tac): fresh30(model(sK49_tac_I2(X), X), true2, Y, X, Z) = fresh29(model(Z, Y), true2, Y, X). 0.13/0.59 Axiom 7 (thm_2): fresh19(model(sK45_thm_I1(X, Y), Y), true2, X, Y) = status(X, Y, thm). 0.13/0.59 Axiom 8 (non_thm_spt_1): model(sK21_non_thm_spt_I2, sK24_non_thm_spt_C) = true2. 0.13/0.59 Axiom 9 (mighta): fresh48(status(X, Y, Z), true2, W, Z, X, Y) = fresh47(status(X, Y, W), true2, W, Z). 0.13/0.59 Axiom 10 (tautology): model(X, sK13_tautology_F) = true2. 0.13/0.59 0.13/0.59 Goal 1 (mighta_tac_thm): mighta(tac, thm) = true2. 0.13/0.59 Proof: 0.13/0.59 mighta(tac, thm) 0.13/0.59 = { by axiom 1 (mighta) } 0.13/0.59 fresh48(true2, true2, tac, thm, sK24_non_thm_spt_C, sK13_tautology_F) 0.13/0.59 = { by axiom 5 (thm_2) } 0.13/0.59 fresh48(fresh19(true2, true2, sK24_non_thm_spt_C, sK13_tautology_F), true2, tac, thm, sK24_non_thm_spt_C, sK13_tautology_F) 0.13/0.59 = { by axiom 10 (tautology) } 0.13/0.59 fresh48(fresh19(model(sK45_thm_I1(sK24_non_thm_spt_C, sK13_tautology_F), sK13_tautology_F), true2, sK24_non_thm_spt_C, sK13_tautology_F), true2, tac, thm, sK24_non_thm_spt_C, sK13_tautology_F) 0.13/0.59 = { by axiom 7 (thm_2) } 0.13/0.59 fresh48(status(sK24_non_thm_spt_C, sK13_tautology_F, thm), true2, tac, thm, sK24_non_thm_spt_C, sK13_tautology_F) 0.13/0.59 = { by axiom 9 (mighta) } 0.13/0.59 fresh47(status(sK24_non_thm_spt_C, sK13_tautology_F, tac), true2, tac, thm) 0.13/0.59 = { by axiom 3 (tac) } 0.13/0.59 fresh47(fresh30(true2, true2, sK24_non_thm_spt_C, sK13_tautology_F, sK21_non_thm_spt_I2), true2, tac, thm) 0.13/0.59 = { by axiom 10 (tautology) } 0.13/0.59 fresh47(fresh30(model(sK49_tac_I2(sK13_tautology_F), sK13_tautology_F), true2, sK24_non_thm_spt_C, sK13_tautology_F, sK21_non_thm_spt_I2), true2, tac, thm) 0.13/0.59 = { by axiom 6 (tac) } 0.13/0.59 fresh47(fresh29(model(sK21_non_thm_spt_I2, sK24_non_thm_spt_C), true2, sK24_non_thm_spt_C, sK13_tautology_F), true2, tac, thm) 0.13/0.59 = { by axiom 8 (non_thm_spt_1) } 0.13/0.59 fresh47(fresh29(true2, true2, sK24_non_thm_spt_C, sK13_tautology_F), true2, tac, thm) 0.13/0.59 = { by axiom 4 (tac) } 0.13/0.59 fresh47(true2, true2, tac, thm) 0.13/0.59 = { by axiom 2 (mighta) } 0.13/0.59 true2 0.13/0.59 % SZS output end Proof 0.13/0.59 0.13/0.59 RESULT: Theorem (the conjecture is true). 0.13/0.59 EOF