0.00/0.03 % Problem : theBenchmark.p : TPTP v0.0.0. Released v0.0.0. 0.03/0.04 % Command : twee %s --tstp --casc --quiet --conditional-encoding if --smaller --drop-non-horn 0.03/0.24 % Computer : n005.star.cs.uiowa.edu 0.03/0.24 % Model : x86_64 x86_64 0.03/0.24 % CPU : Intel(R) Xeon(R) CPU E5-2609 0 @ 2.40GHz 0.03/0.24 % Memory : 32218.625MB 0.03/0.24 % OS : Linux 3.10.0-693.2.2.el7.x86_64 0.03/0.24 % CPULimit : 300 0.03/0.24 % DateTime : Sat Jul 14 04:21:55 CDT 2018 0.03/0.24 % CPUTime : 0.07/0.38 % SZS status Theorem 0.07/0.38 0.07/0.38 % SZS output start Proof 0.07/0.38 Take the following subset of the input axioms: 0.07/0.38 fof(first_second, axiom, 0.07/0.38 ![X, Y]: 0.07/0.38 ((member(Y, universal_class) & member(X, universal_class)) 0.07/0.38 => (first(ordered_pair(X, Y))=X & Y=second(ordered_pair(X, Y))))). 0.07/0.38 fof(unique_1st_and_2nd_in_pair_of_sets1, conjecture, 0.07/0.38 ![X, U, V]: 0.07/0.38 ((member(V, universal_class) 0.07/0.38 & (ordered_pair(U, V)=X & member(U, universal_class))) 0.07/0.38 => (V=second(X) & first(X)=U))). 0.07/0.38 0.07/0.38 Now clausify the problem and encode Horn clauses using encoding 3 of 0.07/0.38 http://www.cse.chalmers.se/~nicsma/papers/horn.pdf. 0.07/0.38 We repeatedly replace C & s=t => u=v by the two clauses: 0.07/0.38 $$fresh(y, y, x1...xn) = u 0.07/0.38 C => $$fresh(s, t, x1...xn) = v 0.07/0.38 where $$fresh is a fresh function symbol and x1..xn are the free 0.07/0.38 variables of u and v. 0.07/0.38 A predicate p(X) is encoded as p(X)=$$true (this is sound, because the 0.07/0.38 input problem has no model of domain size 1). 0.07/0.38 0.07/0.38 The encoding turns the above axioms into the following unit equations and goals: 0.07/0.38 0.07/0.38 Axiom 18 (first_second): $$fresh4(X, X, Y, Z) = Y. 0.07/0.38 Axiom 19 (first_second): $$fresh56(X, X, Y, Z) = first(ordered_pair(Y, Z)). 0.07/0.38 Axiom 20 (first_second_1): $$fresh5(X, X, Y, Z) = Z. 0.07/0.38 Axiom 21 (first_second_1): $$fresh55(X, X, Y, Z) = second(ordered_pair(Y, Z)). 0.07/0.38 Axiom 116 (first_second_1): $$fresh55(member(X, universal_class), $$true2, Y, X) = $$fresh5(member(Y, universal_class), $$true2, Y, X). 0.07/0.38 Axiom 117 (first_second): $$fresh56(member(X, universal_class), $$true2, Y, X) = $$fresh4(member(Y, universal_class), $$true2, Y, X). 0.07/0.38 Axiom 146 (unique_1st_and_2nd_in_pair_of_sets1): ordered_pair(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V) = sK1_unique_1st_and_2nd_in_pair_of_sets1_X. 0.07/0.38 Axiom 147 (unique_1st_and_2nd_in_pair_of_sets1_1): member(sK3_unique_1st_and_2nd_in_pair_of_sets1_V, universal_class) = $$true2. 0.07/0.38 Axiom 148 (unique_1st_and_2nd_in_pair_of_sets1_2): member(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, universal_class) = $$true2. 0.07/0.38 0.07/0.38 Goal 1 (unique_1st_and_2nd_in_pair_of_sets1_3): tuple4(first(sK1_unique_1st_and_2nd_in_pair_of_sets1_X), sK3_unique_1st_and_2nd_in_pair_of_sets1_V) = tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, second(sK1_unique_1st_and_2nd_in_pair_of_sets1_X)). 0.07/0.38 Proof: 0.07/0.38 tuple4(first(sK1_unique_1st_and_2nd_in_pair_of_sets1_X), sK3_unique_1st_and_2nd_in_pair_of_sets1_V) 0.07/0.38 = { by axiom 146 (unique_1st_and_2nd_in_pair_of_sets1) } 0.07/0.38 tuple4(first(ordered_pair(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V)), sK3_unique_1st_and_2nd_in_pair_of_sets1_V) 0.07/0.38 = { by axiom 19 (first_second) } 0.07/0.38 tuple4($$fresh56($$true2, $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V), sK3_unique_1st_and_2nd_in_pair_of_sets1_V) 0.07/0.38 = { by axiom 147 (unique_1st_and_2nd_in_pair_of_sets1_1) } 0.07/0.38 tuple4($$fresh56(member(sK3_unique_1st_and_2nd_in_pair_of_sets1_V, universal_class), $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V), sK3_unique_1st_and_2nd_in_pair_of_sets1_V) 0.07/0.38 = { by axiom 117 (first_second) } 0.07/0.38 tuple4($$fresh4(member(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, universal_class), $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V), sK3_unique_1st_and_2nd_in_pair_of_sets1_V) 0.07/0.38 = { by axiom 148 (unique_1st_and_2nd_in_pair_of_sets1_2) } 0.07/0.38 tuple4($$fresh4($$true2, $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V), sK3_unique_1st_and_2nd_in_pair_of_sets1_V) 0.07/0.38 = { by axiom 18 (first_second) } 0.07/0.38 tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V) 0.07/0.38 = { by axiom 20 (first_second_1) } 0.07/0.38 tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, $$fresh5($$true2, $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V)) 0.07/0.38 = { by axiom 148 (unique_1st_and_2nd_in_pair_of_sets1_2) } 0.07/0.38 tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, $$fresh5(member(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, universal_class), $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V)) 0.07/0.38 = { by axiom 116 (first_second_1) } 0.07/0.38 tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, $$fresh55(member(sK3_unique_1st_and_2nd_in_pair_of_sets1_V, universal_class), $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V)) 0.07/0.38 = { by axiom 147 (unique_1st_and_2nd_in_pair_of_sets1_1) } 0.07/0.38 tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, $$fresh55($$true2, $$true2, sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V)) 0.07/0.38 = { by axiom 21 (first_second_1) } 0.07/0.38 tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, second(ordered_pair(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, sK3_unique_1st_and_2nd_in_pair_of_sets1_V))) 0.07/0.38 = { by axiom 146 (unique_1st_and_2nd_in_pair_of_sets1) } 0.07/0.38 tuple4(sK2_unique_1st_and_2nd_in_pair_of_sets1_U, second(sK1_unique_1st_and_2nd_in_pair_of_sets1_X)) 0.07/0.38 % SZS output end Proof 0.07/0.38 0.07/0.38 RESULT: Theorem (the conjecture is true). 0.07/0.38 EOF