%------------------------------------------------------------------------------ % File : Otter---3.3 % Problem : SWX207+1 : TPTP v9.3.0. Released v9.3.0. % Transfm : none % Format : tptp:raw % Command : otter-tptp-script %s % Computer : n001.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 : Tue May 5 07:05:25 PM UTC 2026 % Result : Unknown 14.11s 14.35s % Output : None % Verified : % SZS Type : - % Comments : %------------------------------------------------------------------------------ %----No solution output by system %------------------------------------------------------------------------------ %----ORIGINAL SYSTEM OUTPUT % 0.00/0.11 % Problem : SWX207+1 : TPTP v9.3.0. Released v9.3.0. % 0.00/0.12 % Command : otter-tptp-script %s % 0.16/0.33 % Computer : n001.cluster.edu % 0.16/0.33 % Model : x86_64 x86_64 % 0.16/0.33 % CPU : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz % 0.16/0.33 % Memory : 8042.1875MB % 0.16/0.33 % OS : Linux 3.10.0-693.el7.x86_64 % 0.16/0.33 % CPULimit : 300 % 0.16/0.33 % WCLimit : 300 % 0.16/0.33 % DateTime : Tue May 5 11:36:18 EDT 2026 % 0.16/0.33 % CPUTime : % 1.89/2.10 ----- Otter 3.3f, August 2004 ----- % 1.89/2.10 The process was started by sandbox2 on n001.cluster.edu, % 1.89/2.10 Tue May 5 11:36:18 2026 % 1.89/2.10 The command was "./otter". The process ID is 15846. % 1.89/2.10 % 1.89/2.10 set(prolog_style_variables). % 1.89/2.10 set(auto). % 1.89/2.10 dependent: set(auto1). % 1.89/2.10 dependent: set(process_input). % 1.89/2.10 dependent: clear(print_kept). % 1.89/2.10 dependent: clear(print_new_demod). % 1.89/2.10 dependent: clear(print_back_demod). % 1.89/2.10 dependent: clear(print_back_sub). % 1.89/2.10 dependent: set(control_memory). % 1.89/2.10 dependent: assign(max_mem, 12000). % 1.89/2.10 dependent: assign(pick_given_ratio, 4). % 1.89/2.10 dependent: assign(stats_level, 1). % 1.89/2.10 dependent: assign(max_seconds, 10800). % 1.89/2.10 clear(print_given). % 1.89/2.10 % 1.89/2.10 formula_list(usable). % 1.89/2.10 all A (A=A). % 1.89/2.10 all X X2 (head(cons(X,X2))=X). % 1.89/2.10 all X X2 (tail(cons(X,X2))=X2). % 1.89/2.10 all X X2 (nil!=cons(X,X2)). % 1.89/2.10 a!=b. % 1.89/2.10 all X (proj1AP(aP(X))=X). % 1.89/2.10 all X (proj1BP(bP(X))=X). % 1.89/2.10 all X X2 (aP(X)!=bP(X2)). % 1.89/2.10 all X (aP(X)!=pA). % 1.89/2.10 all X (aP(X)!=pB). % 1.89/2.10 all X (aP(X)!=pE). % 1.89/2.10 all X (bP(X)!=pA). % 1.89/2.10 all X (bP(X)!=pB). % 1.89/2.10 all X (bP(X)!=pE). % 1.89/2.10 pA!=pB. % 1.89/2.10 pA!=pE. % 1.89/2.10 pB!=pE. % 1.89/2.10 all X X2 (proj1C(c2(X,X2))=X). % 1.89/2.10 all X X2 (proj2C(c2(X,X2))=X2). % 1.89/2.10 all Y (append(nil,Y)=Y). % 1.89/2.10 all Y Z Xs (append(cons(Z,Xs),Y)=cons(Z,append(Xs,Y))). % 1.89/2.10 all P (linP(aP(P))=append(cons(a,nil),append(linP(P),cons(a,nil)))). % 1.89/2.10 all Q (linP(bP(Q))=append(cons(b,nil),append(linP(Q),cons(b,nil)))). % 1.89/2.10 linP(pA)=cons(a,nil). % 1.89/2.10 linP(pB)=cons(b,nil). % 1.89/2.10 linP(pE)=nil. % 1.89/2.10 all P Q (linC(c2(P,Q))=append(linP(P),linP(Q))). % 1.89/2.10 -(exists U V (-(linC(U)=linC(V)->U=V))). % 1.89/2.10 end_of_list. % 1.89/2.10 % 1.89/2.10 -------> usable clausifies to: % 1.89/2.10 % 1.89/2.10 list(usable). % 1.89/2.10 0 [] A=A. % 1.89/2.10 0 [] head(cons(X,X2))=X. % 1.89/2.10 0 [] tail(cons(X,X2))=X2. % 1.89/2.10 0 [] nil!=cons(X,X2). % 1.89/2.10 0 [] a!=b. % 1.89/2.10 0 [] proj1AP(aP(X))=X. % 1.89/2.10 0 [] proj1BP(bP(X))=X. % 1.89/2.10 0 [] aP(X)!=bP(X2). % 1.89/2.10 0 [] aP(X)!=pA. % 1.89/2.10 0 [] aP(X)!=pB. % 1.89/2.10 0 [] aP(X)!=pE. % 1.89/2.10 0 [] bP(X)!=pA. % 1.89/2.10 0 [] bP(X)!=pB. % 1.89/2.10 0 [] bP(X)!=pE. % 1.89/2.10 0 [] pA!=pB. % 1.89/2.10 0 [] pA!=pE. % 1.89/2.10 0 [] pB!=pE. % 1.89/2.10 0 [] proj1C(c2(X,X2))=X. % 1.89/2.10 0 [] proj2C(c2(X,X2))=X2. % 1.89/2.10 0 [] append(nil,Y)=Y. % 1.89/2.10 0 [] append(cons(Z,Xs),Y)=cons(Z,append(Xs,Y)). % 1.89/2.10 0 [] linP(aP(P))=append(cons(a,nil),append(linP(P),cons(a,nil))). % 1.89/2.10 0 [] linP(bP(Q))=append(cons(b,nil),append(linP(Q),cons(b,nil))). % 1.89/2.10 0 [] linP(pA)=cons(a,nil). % 1.89/2.10 0 [] linP(pB)=cons(b,nil). % 1.89/2.10 0 [] linP(pE)=nil. % 1.89/2.10 0 [] linC(c2(P,Q))=append(linP(P),linP(Q)). % 1.89/2.10 0 [] linC(U)!=linC(V)|U=V. % 1.89/2.10 end_of_list. % 1.89/2.10 % 1.89/2.10 SCAN INPUT: prop=0, horn=1, equality=1, symmetry=0, max_lits=2. % 1.89/2.10 % 1.89/2.10 This is a Horn set with equality. The strategy will be % 1.89/2.10 Knuth-Bendix and hyper_res, with positive clauses in % 1.89/2.10 sos and nonpositive clauses in usable. % 1.89/2.10 % 1.89/2.10 dependent: set(knuth_bendix). % 1.89/2.10 dependent: set(anl_eq). % 1.89/2.10 dependent: set(para_from). % 1.89/2.10 dependent: set(para_into). % 1.89/2.10 dependent: clear(para_from_right). % 1.89/2.10 dependent: clear(para_into_right). % 1.89/2.10 dependent: set(para_from_vars). % 1.89/2.10 dependent: set(eq_units_both_ways). % 1.89/2.10 dependent: set(dynamic_demod_all). % 1.89/2.10 dependent: set(dynamic_demod). % 1.89/2.10 dependent: set(order_eq). % 1.89/2.10 dependent: set(back_demod). % 1.89/2.10 dependent: set(lrpo). % 1.89/2.10 dependent: set(hyper_res). % 1.89/2.10 dependent: clear(order_hyper). % 1.89/2.10 % 1.89/2.10 ------------> process usable: % 1.89/2.10 ** KEPT (pick-wt=5): 2 [copy,1,flip.1] cons(A,B)!=nil. % 1.89/2.10 ** KEPT (pick-wt=3): 4 [copy,3,flip.1] b!=a. % 1.89/2.10 ** KEPT (pick-wt=5): 5 [] aP(A)!=bP(B). % 1.89/2.10 ** KEPT (pick-wt=4): 6 [] aP(A)!=pA. % 1.89/2.10 ** KEPT (pick-wt=4): 7 [] aP(A)!=pB. % 1.89/2.10 ** KEPT (pick-wt=4): 8 [] aP(A)!=pE. % 1.89/2.10 ** KEPT (pick-wt=4): 9 [] bP(A)!=pA. % 1.89/2.10 ** KEPT (pick-wt=4): 10 [] bP(A)!=pB. % 1.89/2.10 ** KEPT (pick-wt=4): 11 [] bP(A)!=pE. % 1.89/2.10 ** KEPT (pick-wt=3): 13 [copy,12,flip.1] pB!=pA. % 1.89/2.10 ** KEPT (pick-wt=3): 15 [copy,14,flip.1] pE!=pA. % 1.89/2.10 ** KEPT (pick-wt=3): 17 [copy,16,flip.1] pE!=pB. % 1.89/2.10 ** KEPT (pick-wt=8): 18 [] linC(A)!=linC(B)|A=B. % 1.89/2.10 ** KEPT (pick-wt=5): 19 [copy,5,flip.1] bP(A)!=aP(B). % 1.89/2.10 Following clause subsumed by 5 during input processing: 0 [copy,19,flip.1] aP(A)!=bP(B). % 1.89/2.10 % 1.89/2.10 ------------> process sos: % 1.89/2.10 ** KEPT (pick-wt=3): 20 [] A=A. % 1.89/2.10 ** KEPT (pick-wt=6): 21 [] head(cons(A,B))=A. % 1.89/2.10 ---> New Demodulator: 22 [new_demod,21] head(cons(A,B))=A. % 1.89/2.10 ** KEPT (pick-wt=6): 23 [] tail(cons(A,B))=B. % 1.89/2.10 ---> New Demodulator: 24 [new_demod,23] tail(cons(A,B))=B. % 1.89/2.10 ** KEPT (pick-wt=5): 25 [] proj1AP(aP(A))=A. % 1.89/2.10 ---> New Demodulator: 26 [new_demod,25] proj1AP(aP(A))=A. % 1.89/2.10 ** KEPT (pick-wt=5): 27 [] proj1BP(bP(A))=A. % 1.89/2.10 ---> New Demodulator: 28 [new_demod,27] proj1BP(bP(A))=A. % 14.11/14.35 ** KEPT (pick-wt=6): 29 [] proj1C(c2(A,B))=A. % 14.11/14.35 ---> New Demodulator: 30 [new_demod,29] proj1C(c2(A,B))=A. % 14.11/14.35 ** KEPT (pick-wt=6): 31 [] proj2C(c2(A,B))=B. % 14.11/14.35 ---> New Demodulator: 32 [new_demod,31] proj2C(c2(A,B))=B. % 14.11/14.35 ** KEPT (pick-wt=5): 33 [] append(nil,A)=A. % 14.11/14.35 ---> New Demodulator: 34 [new_demod,33] append(nil,A)=A. % 14.11/14.35 ** KEPT (pick-wt=11): 36 [copy,35,flip.1] cons(A,append(B,C))=append(cons(A,B),C). % 14.11/14.35 ---> New Demodulator: 37 [new_demod,36] cons(A,append(B,C))=append(cons(A,B),C). % 14.11/14.35 ** KEPT (pick-wt=14): 38 [] linP(aP(A))=append(cons(a,nil),append(linP(A),cons(a,nil))). % 14.11/14.35 ---> New Demodulator: 39 [new_demod,38] linP(aP(A))=append(cons(a,nil),append(linP(A),cons(a,nil))). % 14.11/14.35 ** KEPT (pick-wt=14): 40 [] linP(bP(A))=append(cons(b,nil),append(linP(A),cons(b,nil))). % 14.11/14.35 ---> New Demodulator: 41 [new_demod,40] linP(bP(A))=append(cons(b,nil),append(linP(A),cons(b,nil))). % 14.11/14.35 ** KEPT (pick-wt=6): 42 [] linP(pA)=cons(a,nil). % 14.11/14.35 ---> New Demodulator: 43 [new_demod,42] linP(pA)=cons(a,nil). % 14.11/14.35 ** KEPT (pick-wt=6): 44 [] linP(pB)=cons(b,nil). % 14.11/14.35 ---> New Demodulator: 45 [new_demod,44] linP(pB)=cons(b,nil). % 14.11/14.35 ** KEPT (pick-wt=4): 46 [] linP(pE)=nil. % 14.11/14.35 ---> New Demodulator: 47 [new_demod,46] linP(pE)=nil. % 14.11/14.35 ** KEPT (pick-wt=10): 48 [] linC(c2(A,B))=append(linP(A),linP(B)). % 14.11/14.35 Following clause subsumed by 20 during input processing: 0 [copy,20,flip.1] A=A. % 14.11/14.35 >>>> Starting back demodulation with 22. % 14.11/14.35 >>>> Starting back demodulation with 24. % 14.11/14.35 >>>> Starting back demodulation with 26. % 14.11/14.35 >>>> Starting back demodulation with 28. % 14.11/14.35 >>>> Starting back demodulation with 30. % 14.11/14.35 >>>> Starting back demodulation with 32. % 14.11/14.35 >>>> Starting back demodulation with 34. % 14.11/14.35 >>>> Starting back demodulation with 37. % 14.11/14.35 >>>> Starting back demodulation with 39. % 14.11/14.35 >>>> Starting back demodulation with 41. % 14.11/14.35 >>>> Starting back demodulation with 43. % 14.11/14.35 >>>> Starting back demodulation with 45. % 14.11/14.35 >>>> Starting back demodulation with 47. % 14.11/14.35 ** KEPT (pick-wt=10): 49 [copy,48,flip.1] append(linP(A),linP(B))=linC(c2(A,B)). % 14.11/14.35 Following clause subsumed by 48 during input processing: 0 [copy,49,flip.1] linC(c2(A,B))=append(linP(A),linP(B)). % 14.11/14.35 % 14.11/14.35 ======= end of input processing ======= % 14.11/14.35 % 14.11/14.35 =========== start of search =========== % 14.11/14.35 % 14.11/14.35 % 14.11/14.35 Resetting weight limit to 12. % 14.11/14.35 % 14.11/14.35 % 14.11/14.35 Resetting weight limit to 12. % 14.11/14.35 % 14.11/14.35 sos_size=1589 % 14.11/14.35 % 14.11/14.35 % 14.11/14.35 Resetting weight limit to 11. % 14.11/14.35 % 14.11/14.35 % 14.11/14.35 Resetting weight limit to 11. % 14.11/14.35 % 14.11/14.35 sos_size=1625 % 14.11/14.35 % 14.11/14.35 Search stopped because sos empty. % 14.11/14.35 % 14.11/14.35 % 14.11/14.35 Search stopped because sos empty. % 14.11/14.35 % 14.11/14.35 ============ end of search ============ % 14.11/14.35 % 14.11/14.35 -------------- statistics ------------- % 14.11/14.35 clauses given 1946 % 14.11/14.35 clauses generated 2470215 % 14.11/14.35 clauses kept 2390 % 14.11/14.35 clauses forward subsumed 4395 % 14.11/14.35 clauses back subsumed 434 % 14.11/14.35 Kbytes malloced 7812 % 14.11/14.35 % 14.11/14.35 ----------- times (seconds) ----------- % 14.11/14.35 user CPU time 12.24 (0 hr, 0 min, 12 sec) % 14.11/14.35 system CPU time 0.01 (0 hr, 0 min, 0 sec) % 14.11/14.35 wall-clock time 14 (0 hr, 0 min, 14 sec) % 14.11/14.35 % 14.11/14.35 Process 15846 finished Tue May 5 11:36:32 2026 % 14.11/14.35 Otter interrupted % 14.11/14.35 PROOF NOT FOUND %------------------------------------------------------------------------------