TSTP Solution File: GRP295-1 by SPASS---3.9

View Problem - Process Solution

%------------------------------------------------------------------------------
% File     : SPASS---3.9
% Problem  : GRP295-1 : TPTP v8.1.0. Released v2.5.0.
% Transfm  : none
% Format   : tptp
% Command  : run_spass %d %s

% Computer : n021.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  : 600s
% DateTime : Sat Jul 16 11:46:43 EDT 2022

% Result   : Unsatisfiable 0.21s 0.47s
% Output   : Refutation 0.21s
% Verified : 
% SZS Type : -

% Comments : 
%------------------------------------------------------------------------------
%----WARNING: Could not form TPTP format derivation
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.07/0.12  % Problem  : GRP295-1 : TPTP v8.1.0. Released v2.5.0.
% 0.07/0.13  % Command  : run_spass %d %s
% 0.14/0.35  % Computer : n021.cluster.edu
% 0.14/0.35  % Model    : x86_64 x86_64
% 0.14/0.35  % CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.14/0.35  % Memory   : 8042.1875MB
% 0.14/0.35  % OS       : Linux 3.10.0-693.el7.x86_64
% 0.14/0.35  % CPULimit : 300
% 0.14/0.35  % WCLimit  : 600
% 0.14/0.35  % DateTime : Mon Jun 13 08:04:42 EDT 2022
% 0.14/0.35  % CPUTime  : 
% 0.21/0.47  
% 0.21/0.47  SPASS V 3.9 
% 0.21/0.47  SPASS beiseite: Proof found.
% 0.21/0.47  % SZS status Theorem
% 0.21/0.47  Problem: /export/starexec/sandbox/benchmark/theBenchmark.p 
% 0.21/0.47  SPASS derived 713 clauses, backtracked 348 clauses, performed 11 splits and kept 639 clauses.
% 0.21/0.47  SPASS allocated 63567 KBytes.
% 0.21/0.47  SPASS spent	0:00:00.12 on the problem.
% 0.21/0.47  		0:00:00.04 for the input.
% 0.21/0.47  		0:00:00.00 for the FLOTTER CNF translation.
% 0.21/0.47  		0:00:00.00 for inferences.
% 0.21/0.47  		0:00:00.00 for the backtracking.
% 0.21/0.47  		0:00:00.05 for the reduction.
% 0.21/0.47  
% 0.21/0.47  
% 0.21/0.47  Here is a proof with depth 5, length 300 :
% 0.21/0.47  % SZS output start Refutation
% 0.21/0.47  1[0:Inp] ||  -> equal(multiply(sk_c6,sk_c7),sk_c5)** equal(multiply(sk_c7,sk_c6),sk_c5).
% 0.21/0.47  2[0:Inp] ||  -> equal(inverse(sk_c3),sk_c7) equal(multiply(sk_c7,sk_c6),sk_c5)**.
% 0.21/0.47  4[0:Inp] ||  -> equal(inverse(sk_c4),sk_c6) equal(multiply(sk_c7,sk_c6),sk_c5)**.
% 0.21/0.47  7[0:Inp] ||  -> equal(inverse(sk_c3),sk_c7) equal(multiply(sk_c1,sk_c7),sk_c6)**.
% 0.21/0.47  8[0:Inp] ||  -> equal(multiply(sk_c3,sk_c6),sk_c7) equal(multiply(sk_c1,sk_c7),sk_c6)**.
% 0.21/0.47  9[0:Inp] ||  -> equal(inverse(sk_c4),sk_c6) equal(multiply(sk_c1,sk_c7),sk_c6)**.
% 0.21/0.47  12[0:Inp] ||  -> equal(inverse(sk_c3),sk_c7) equal(inverse(sk_c1),sk_c7)**.
% 0.21/0.47  13[0:Inp] ||  -> equal(inverse(sk_c1),sk_c7) equal(multiply(sk_c3,sk_c6),sk_c7)**.
% 0.21/0.47  14[0:Inp] ||  -> equal(inverse(sk_c4),sk_c6) equal(inverse(sk_c1),sk_c7)**.
% 0.21/0.47  16[0:Inp] ||  -> equal(multiply(sk_c6,sk_c7),sk_c5)** equal(multiply(sk_c7,sk_c5),sk_c6).
% 0.21/0.47  17[0:Inp] ||  -> equal(inverse(sk_c3),sk_c7) equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  18[0:Inp] ||  -> equal(multiply(sk_c3,sk_c6),sk_c7)** equal(multiply(sk_c7,sk_c5),sk_c6).
% 0.21/0.47  19[0:Inp] ||  -> equal(inverse(sk_c4),sk_c6) equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  20[0:Inp] ||  -> equal(multiply(sk_c4,sk_c5),sk_c6)** equal(multiply(sk_c7,sk_c5),sk_c6).
% 0.21/0.47  21[0:Inp] ||  -> equal(multiply(sk_c6,sk_c7),sk_c5) equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  22[0:Inp] ||  -> equal(inverse(sk_c3),sk_c7) equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  23[0:Inp] ||  -> equal(multiply(sk_c3,sk_c6),sk_c7) equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  24[0:Inp] ||  -> equal(inverse(sk_c4),sk_c6) equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  25[0:Inp] ||  -> equal(multiply(sk_c4,sk_c5),sk_c6) equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  26[0:Inp] ||  -> equal(inverse(sk_c2),sk_c7) equal(multiply(sk_c6,sk_c7),sk_c5)**.
% 0.21/0.47  27[0:Inp] ||  -> equal(inverse(sk_c3),sk_c7) equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  28[0:Inp] ||  -> equal(inverse(sk_c2),sk_c7) equal(multiply(sk_c3,sk_c6),sk_c7)**.
% 0.21/0.47  29[0:Inp] ||  -> equal(inverse(sk_c4),sk_c6) equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  30[0:Inp] ||  -> equal(inverse(sk_c2),sk_c7) equal(multiply(sk_c4,sk_c5),sk_c6)**.
% 0.21/0.47  31[0:Inp] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(inverse(x),sk_c7) equal(multiply(u,sk_c5),sk_c6)**+ equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c5)** equal(multiply(x,sk_c7),sk_c6)** equal(multiply(sk_c6,sk_c7),sk_c5)** equal(multiply(sk_c7,sk_c5),sk_c6) equal(multiply(sk_c7,sk_c6),sk_c5) -> .
% 0.21/0.47  32[0:Inp] ||  -> equal(multiply(identity,u),u)**.
% 0.21/0.47  33[0:Inp] ||  -> equal(multiply(inverse(u),u),identity)**.
% 0.21/0.47  34[0:Inp] ||  -> equal(multiply(multiply(u,v),w),multiply(u,multiply(v,w)))**.
% 0.21/0.47  35[1:Spt:31.2,31.6] || equal(inverse(u),sk_c7) equal(multiply(u,sk_c7),sk_c5)** -> .
% 0.21/0.47  36[2:Spt:16.0] ||  -> equal(multiply(sk_c6,sk_c7),sk_c5)**.
% 0.21/0.47  38[2:SpL:36.0,35.1] || equal(inverse(sk_c6),sk_c7)** equal(sk_c5,sk_c5) -> .
% 0.21/0.47  39[2:Obv:38.1] || equal(inverse(sk_c6),sk_c7)** -> .
% 0.21/0.47  40[3:Spt:19.0] ||  -> equal(inverse(sk_c4),sk_c6)**.
% 0.21/0.47  42[4:Spt:17.0] ||  -> equal(inverse(sk_c3),sk_c7)**.
% 0.21/0.47  44[5:Spt:20.0] ||  -> equal(multiply(sk_c4,sk_c5),sk_c6)**.
% 0.21/0.47  46[6:Spt:18.0] ||  -> equal(multiply(sk_c3,sk_c6),sk_c7)**.
% 0.21/0.47  49[1:SpL:32.0,35.1] || equal(inverse(identity),sk_c7)** equal(sk_c5,sk_c7) -> .
% 0.21/0.47  51[3:SpR:40.0,33.0] ||  -> equal(multiply(sk_c6,sk_c4),identity)**.
% 0.21/0.47  52[4:SpR:42.0,33.0] ||  -> equal(multiply(sk_c7,sk_c3),identity)**.
% 0.21/0.47  61[0:SpR:33.0,34.0] ||  -> equal(multiply(inverse(u),multiply(u,v)),multiply(identity,v))**.
% 0.21/0.47  62[3:SpR:51.0,34.0] ||  -> equal(multiply(sk_c6,multiply(sk_c4,u)),multiply(identity,u))**.
% 0.21/0.47  64[3:Rew:32.0,62.0] ||  -> equal(multiply(sk_c6,multiply(sk_c4,u)),u)**.
% 0.21/0.47  65[0:Rew:32.0,61.0] ||  -> equal(multiply(inverse(u),multiply(u,v)),v)**.
% 0.21/0.47  67[4:SpR:52.0,34.0] ||  -> equal(multiply(sk_c7,multiply(sk_c3,u)),multiply(identity,u))**.
% 0.21/0.47  69[4:Rew:32.0,67.0] ||  -> equal(multiply(sk_c7,multiply(sk_c3,u)),u)**.
% 0.21/0.47  72[5:SpR:44.0,64.0] ||  -> equal(multiply(sk_c6,sk_c6),sk_c5)**.
% 0.21/0.47  78[6:SpR:46.0,69.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c6)**.
% 0.21/0.47  81[0:SpR:65.0,65.0] ||  -> equal(multiply(inverse(inverse(u)),v),multiply(u,v))**.
% 0.21/0.47  83[2:SpR:36.0,65.0] ||  -> equal(multiply(inverse(sk_c6),sk_c5),sk_c7)**.
% 0.21/0.47  87[0:SpR:33.0,65.0] ||  -> equal(multiply(inverse(inverse(u)),identity),u)**.
% 0.21/0.47  88[3:SpR:51.0,65.0] ||  -> equal(multiply(inverse(sk_c6),identity),sk_c4)**.
% 0.21/0.47  90[5:SpR:72.0,65.0] ||  -> equal(multiply(inverse(sk_c6),sk_c5),sk_c6)**.
% 0.21/0.47  92[4:SpR:52.0,65.0] ||  -> equal(multiply(inverse(sk_c7),identity),sk_c3)**.
% 0.21/0.47  98[5:Rew:83.0,90.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  99[5:Rew:98.0,36.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.47  100[5:Rew:98.0,40.0] ||  -> equal(inverse(sk_c4),sk_c7)**.
% 0.21/0.47  101[5:Rew:98.0,39.0] || equal(inverse(sk_c7),sk_c7)** -> .
% 0.21/0.47  104[5:Rew:98.0,51.0] ||  -> equal(multiply(sk_c7,sk_c4),identity)**.
% 0.21/0.47  111[6:Rew:98.0,78.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c7)**.
% 0.21/0.47  112[5:Rew:98.0,83.0] ||  -> equal(multiply(inverse(sk_c7),sk_c5),sk_c7)**.
% 0.21/0.47  114[6:Rew:99.0,111.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.47  121[6:Rew:114.0,112.0] ||  -> equal(multiply(inverse(sk_c7),sk_c7),sk_c7)**.
% 0.21/0.47  122[6:Rew:33.0,121.0] ||  -> equal(identity,sk_c7)**.
% 0.21/0.47  123[6:Rew:122.0,32.0] ||  -> equal(multiply(sk_c7,u),u)**.
% 0.21/0.47  127[6:Rew:122.0,104.0] ||  -> equal(multiply(sk_c7,sk_c4),sk_c7)**.
% 0.21/0.47  134[6:Rew:123.0,127.0] ||  -> equal(sk_c4,sk_c7)**.
% 0.21/0.47  135[6:Rew:134.0,100.0] ||  -> equal(inverse(sk_c7),sk_c7)**.
% 0.21/0.47  137[6:MRR:135.0,101.0] ||  -> .
% 0.21/0.47  159[6:Spt:137.0,18.0,46.0] || equal(multiply(sk_c3,sk_c6),sk_c7)** -> .
% 0.21/0.47  160[6:Spt:137.0,18.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  161[6:Rew:98.0,160.0] ||  -> equal(multiply(sk_c7,sk_c5),sk_c7)**.
% 0.21/0.47  166[6:Rew:98.0,159.0] || equal(multiply(sk_c3,sk_c7),sk_c7)** -> .
% 0.21/0.47  167[0:Rew:81.0,87.0] ||  -> equal(multiply(u,identity),u)**.
% 0.21/0.47  168[4:Rew:167.0,92.0] ||  -> equal(inverse(sk_c7),sk_c3)**.
% 0.21/0.47  177[5:Rew:98.0,13.1] ||  -> equal(inverse(sk_c1),sk_c7) equal(multiply(sk_c3,sk_c7),sk_c7)**.
% 0.21/0.47  178[6:MRR:177.1,166.0] ||  -> equal(inverse(sk_c1),sk_c7)**.
% 0.21/0.47  182[5:Rew:98.0,8.1,98.0,8.0] ||  -> equal(multiply(sk_c3,sk_c7),sk_c7) equal(multiply(sk_c1,sk_c7),sk_c7)**.
% 0.21/0.47  183[6:MRR:182.0,166.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c7)**.
% 0.21/0.47  211[6:SpR:161.0,65.0] ||  -> equal(multiply(inverse(sk_c7),sk_c7),sk_c5)**.
% 0.21/0.47  213[6:Rew:168.0,211.0] ||  -> equal(multiply(sk_c3,sk_c7),sk_c5)**.
% 0.21/0.47  214[6:Rew:213.0,166.0] || equal(sk_c5,sk_c7)** -> .
% 0.21/0.47  220[6:SpR:183.0,65.0] ||  -> equal(multiply(inverse(sk_c1),sk_c7),sk_c7)**.
% 0.21/0.47  222[6:Rew:99.0,220.0,178.0,220.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.47  223[6:MRR:222.0,214.0] ||  -> .
% 0.21/0.47  224[5:Spt:223.0,20.0,44.0] || equal(multiply(sk_c4,sk_c5),sk_c6)** -> .
% 0.21/0.47  225[5:Spt:223.0,20.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  226[3:Rew:167.0,88.0] ||  -> equal(inverse(sk_c6),sk_c4)**.
% 0.21/0.47  228[3:Rew:226.0,83.0] ||  -> equal(multiply(sk_c4,sk_c5),sk_c7)**.
% 0.21/0.47  229[5:Rew:228.0,224.0] || equal(sk_c6,sk_c7)** -> .
% 0.21/0.47  231[3:Rew:228.0,30.1] ||  -> equal(inverse(sk_c2),sk_c7)** equal(sk_c6,sk_c7).
% 0.21/0.47  232[5:MRR:231.1,229.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  235[3:Rew:228.0,25.0] ||  -> equal(sk_c6,sk_c7) equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  236[5:MRR:235.0,229.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  247[3:SpR:226.0,65.0] ||  -> equal(multiply(sk_c4,multiply(sk_c6,u)),u)**.
% 0.21/0.47  262[3:SpR:228.0,34.0] ||  -> equal(multiply(sk_c4,multiply(sk_c5,u)),multiply(sk_c7,u))**.
% 0.21/0.47  267[5:SpR:236.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.47  269[5:Rew:225.0,267.0,232.0,267.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  270[5:MRR:269.0,229.0] ||  -> .
% 0.21/0.47  271[4:Spt:270.0,17.0,42.0] || equal(inverse(sk_c3),sk_c7)** -> .
% 0.21/0.47  272[4:Spt:270.0,17.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  273[4:MRR:27.0,271.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  274[4:MRR:12.0,271.0] ||  -> equal(inverse(sk_c1),sk_c7)**.
% 0.21/0.47  275[4:MRR:22.0,271.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  276[4:MRR:7.0,271.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c6)**.
% 0.21/0.47  286[4:SpR:275.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.47  288[4:Rew:272.0,286.0,273.0,286.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  289[4:Rew:288.0,40.0] ||  -> equal(inverse(sk_c4),sk_c7)**.
% 0.21/0.47  291[4:Rew:288.0,51.0] ||  -> equal(multiply(sk_c7,sk_c4),identity)**.
% 0.21/0.47  292[4:Rew:288.0,36.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.47  296[4:Rew:288.0,247.0] ||  -> equal(multiply(sk_c4,multiply(sk_c7,u)),u)**.
% 0.21/0.47  298[4:Rew:288.0,276.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c7)**.
% 0.21/0.47  306[4:SpR:298.0,65.0] ||  -> equal(multiply(inverse(sk_c1),sk_c7),sk_c7)**.
% 0.21/0.47  308[4:Rew:274.0,306.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c7)**.
% 0.21/0.47  309[4:Rew:292.0,308.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.47  314[4:Rew:309.0,49.1] || equal(inverse(identity),sk_c7)** equal(sk_c7,sk_c7) -> .
% 0.21/0.47  315[4:Rew:309.0,262.0] ||  -> equal(multiply(sk_c4,multiply(sk_c7,u)),multiply(sk_c7,u))**.
% 0.21/0.47  323[4:Obv:314.1] || equal(inverse(identity),sk_c7)** -> .
% 0.21/0.47  324[4:Rew:296.0,315.0] ||  -> equal(multiply(sk_c7,u),u)**.
% 0.21/0.47  326[4:Rew:324.0,291.0] ||  -> equal(identity,sk_c4)**.
% 0.21/0.47  334[4:Rew:326.0,323.0] || equal(inverse(sk_c4),sk_c7)** -> .
% 0.21/0.47  337[4:Rew:289.0,334.0] || equal(sk_c7,sk_c7)* -> .
% 0.21/0.47  338[4:Obv:337.0] ||  -> .
% 0.21/0.47  340[3:Spt:338.0,19.0,40.0] || equal(inverse(sk_c4),sk_c6)** -> .
% 0.21/0.47  341[3:Spt:338.0,19.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  342[3:MRR:29.0,340.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  344[3:MRR:24.0,340.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  348[3:SpR:341.0,65.0] ||  -> equal(multiply(inverse(sk_c7),sk_c6),sk_c5)**.
% 0.21/0.47  358[3:SpR:344.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.47  360[3:Rew:341.0,358.0,342.0,358.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  363[3:Rew:360.0,39.0] || equal(inverse(sk_c7),sk_c7)** -> .
% 0.21/0.47  365[3:Rew:360.0,83.0] ||  -> equal(multiply(inverse(sk_c7),sk_c5),sk_c7)**.
% 0.21/0.47  369[3:Rew:360.0,348.0] ||  -> equal(multiply(inverse(sk_c7),sk_c7),sk_c5)**.
% 0.21/0.47  371[3:Rew:33.0,369.0] ||  -> equal(identity,sk_c5)**.
% 0.21/0.47  372[3:Rew:371.0,167.0] ||  -> equal(multiply(u,sk_c5),u)**.
% 0.21/0.47  378[3:Rew:372.0,365.0] ||  -> equal(inverse(sk_c7),sk_c7)**.
% 0.21/0.47  379[3:MRR:378.0,363.0] ||  -> .
% 0.21/0.47  384[2:Spt:379.0,16.0,36.0] || equal(multiply(sk_c6,sk_c7),sk_c5)** -> .
% 0.21/0.47  385[2:Spt:379.0,16.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  386[2:MRR:26.1,384.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  388[2:MRR:21.0,384.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  390[2:MRR:1.0,384.0] ||  -> equal(multiply(sk_c7,sk_c6),sk_c5)**.
% 0.21/0.47  399[2:SpR:388.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.47  401[2:Rew:385.0,399.0,386.0,399.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  403[2:Rew:401.0,384.0] || equal(multiply(sk_c7,sk_c7),sk_c5)** -> .
% 0.21/0.47  405[2:Rew:401.0,390.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.47  408[2:Rew:405.0,403.0] || equal(sk_c5,sk_c5)* -> .
% 0.21/0.47  409[2:Obv:408.0] ||  -> .
% 0.21/0.47  420[1:Spt:409.0,31.0,31.1,31.3,31.4,31.5,31.7,31.8,31.9,31.10] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)**+ equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** equal(multiply(sk_c6,sk_c7),sk_c5)** equal(multiply(sk_c7,sk_c5),sk_c6) equal(multiply(sk_c7,sk_c6),sk_c5) -> .
% 0.21/0.47  422[2:Spt:1.0] ||  -> equal(multiply(sk_c6,sk_c7),sk_c5)**.
% 0.21/0.47  423[2:Rew:422.0,420.6] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** equal(sk_c5,sk_c5) equal(multiply(sk_c7,sk_c5),sk_c6)** equal(multiply(sk_c7,sk_c6),sk_c5) -> .
% 0.21/0.47  425[2:Obv:423.6] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** equal(multiply(sk_c7,sk_c5),sk_c6)** equal(multiply(sk_c7,sk_c6),sk_c5) -> .
% 0.21/0.47  428[2:SpR:422.0,65.0] ||  -> equal(multiply(inverse(sk_c6),sk_c5),sk_c7)**.
% 0.21/0.47  430[3:Spt:17.0] ||  -> equal(inverse(sk_c3),sk_c7)**.
% 0.21/0.47  433[4:Spt:19.0] ||  -> equal(inverse(sk_c4),sk_c6)**.
% 0.21/0.47  436[5:Spt:18.0] ||  -> equal(multiply(sk_c3,sk_c6),sk_c7)**.
% 0.21/0.47  438[5:SpR:436.0,65.0] ||  -> equal(multiply(inverse(sk_c3),sk_c7),sk_c6)**.
% 0.21/0.47  440[5:Rew:430.0,438.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c6)**.
% 0.21/0.47  444[6:Spt:20.0] ||  -> equal(multiply(sk_c4,sk_c5),sk_c6)**.
% 0.21/0.47  446[6:SpR:444.0,65.0] ||  -> equal(multiply(inverse(sk_c4),sk_c6),sk_c5)**.
% 0.21/0.47  448[6:Rew:433.0,446.0] ||  -> equal(multiply(sk_c6,sk_c6),sk_c5)**.
% 0.21/0.47  450[5:SpR:440.0,65.0] ||  -> equal(multiply(inverse(sk_c7),sk_c6),sk_c7)**.
% 0.21/0.47  453[6:SpR:448.0,65.0] ||  -> equal(multiply(inverse(sk_c6),sk_c5),sk_c6)**.
% 0.21/0.47  455[6:Rew:428.0,453.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  456[6:Rew:455.0,422.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.47  457[6:Rew:455.0,433.0] ||  -> equal(inverse(sk_c4),sk_c7)**.
% 0.21/0.47  459[6:Rew:455.0,444.0] ||  -> equal(multiply(sk_c4,sk_c5),sk_c7)**.
% 0.21/0.47  460[6:Rew:455.0,440.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c7)**.
% 0.21/0.47  463[6:Rew:455.0,425.6] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** equal(multiply(sk_c7,sk_c5),sk_c7)** equal(multiply(sk_c7,sk_c6),sk_c5) -> .
% 0.21/0.47  464[6:Rew:455.0,428.0] ||  -> equal(multiply(inverse(sk_c7),sk_c5),sk_c7)**.
% 0.21/0.47  471[6:Rew:456.0,460.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.47  473[6:Rew:471.0,459.0] ||  -> equal(multiply(sk_c4,sk_c7),sk_c7)**.
% 0.21/0.47  475[6:Rew:33.0,464.0,471.0,464.0] ||  -> equal(identity,sk_c7)**.
% 0.21/0.47  476[6:Rew:475.0,32.0] ||  -> equal(multiply(sk_c7,u),u)**.
% 0.21/0.47  477[6:Rew:475.0,167.0] ||  -> equal(multiply(u,sk_c7),u)**.
% 0.21/0.47  481[6:Rew:477.0,473.0] ||  -> equal(sk_c4,sk_c7)**.
% 0.21/0.47  483[6:Rew:481.0,457.0] ||  -> equal(inverse(sk_c7),sk_c7)**.
% 0.21/0.47  493[6:Rew:455.0,463.7,476.0,463.7,471.0,463.7,471.0,463.6,476.0,463.6,477.0,463.5,455.0,463.5,477.0,463.4,455.0,463.4,477.0,463.3,471.0,463.3,455.0,463.3,455.0,463.0] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7)** equal(inverse(w),sk_c7)** equal(u,sk_c7) equal(v,sk_c7) equal(w,sk_c7) equal(sk_c7,sk_c7) equal(sk_c7,sk_c7) -> .
% 0.21/0.47  494[6:Obv:493.7] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7)** equal(inverse(w),sk_c7)** equal(u,sk_c7) equal(v,sk_c7) equal(w,sk_c7) -> .
% 0.21/0.47  495[6:Con:494.1] || equal(inverse(u),sk_c7)** equal(u,sk_c7) -> .
% 0.21/0.47  556[6:SpL:483.0,495.0] || equal(sk_c7,sk_c7)* equal(sk_c7,sk_c7)* -> .
% 0.21/0.47  558[6:Obv:556.1] ||  -> .
% 0.21/0.47  559[6:Spt:558.0,20.0,444.0] || equal(multiply(sk_c4,sk_c5),sk_c6)** -> .
% 0.21/0.47  560[6:Spt:558.0,20.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  561[6:MRR:30.1,559.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  563[6:MRR:25.0,559.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  571[6:SpR:560.0,65.0] ||  -> equal(multiply(inverse(sk_c7),sk_c6),sk_c5)**.
% 0.21/0.47  573[6:Rew:450.0,571.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.47  577[6:Rew:573.0,559.0] || equal(multiply(sk_c4,sk_c7),sk_c6)** -> .
% 0.21/0.47  579[6:Rew:573.0,563.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c7)**.
% 0.21/0.47  608[6:SpR:579.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c7),sk_c7)**.
% 0.21/0.47  610[6:Rew:440.0,608.0,561.0,608.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  611[6:Rew:610.0,433.0] ||  -> equal(inverse(sk_c4),sk_c7)**.
% 0.21/0.47  616[6:Rew:610.0,450.0] ||  -> equal(multiply(inverse(sk_c7),sk_c7),sk_c7)**.
% 0.21/0.47  623[6:Rew:610.0,577.0] || equal(multiply(sk_c4,sk_c7),sk_c7)** -> .
% 0.21/0.47  627[6:Rew:33.0,616.0] ||  -> equal(identity,sk_c7)**.
% 0.21/0.47  628[6:Rew:627.0,32.0] ||  -> equal(multiply(sk_c7,u),u)**.
% 0.21/0.47  629[6:Rew:627.0,167.0] ||  -> equal(multiply(u,sk_c7),u)**.
% 0.21/0.47  630[6:Rew:627.0,33.0] ||  -> equal(multiply(inverse(u),u),sk_c7)**.
% 0.21/0.47  645[6:Rew:629.0,623.0] || equal(sk_c4,sk_c7)** -> .
% 0.21/0.47  675[6:SpR:611.0,630.0] ||  -> equal(multiply(sk_c7,sk_c4),sk_c7)**.
% 0.21/0.47  676[6:Rew:628.0,675.0] ||  -> equal(sk_c4,sk_c7)**.
% 0.21/0.47  677[6:MRR:676.0,645.0] ||  -> .
% 0.21/0.47  681[5:Spt:677.0,18.0,436.0] || equal(multiply(sk_c3,sk_c6),sk_c7)** -> .
% 0.21/0.47  682[5:Spt:677.0,18.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.47  683[5:MRR:28.1,681.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.47  684[5:MRR:13.1,681.0] ||  -> equal(inverse(sk_c1),sk_c7)**.
% 0.21/0.47  685[5:MRR:23.0,681.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.47  686[5:MRR:8.0,681.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c6)**.
% 0.21/0.47  693[5:SpR:682.0,65.0] ||  -> equal(multiply(inverse(sk_c7),sk_c6),sk_c5)**.
% 0.21/0.47  704[5:SpR:685.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.47  706[5:Rew:682.0,704.0,683.0,704.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.47  709[5:Rew:706.0,422.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.48  711[5:Rew:706.0,681.0] || equal(multiply(sk_c3,sk_c7),sk_c7)** -> .
% 0.21/0.48  714[5:Rew:706.0,686.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c7)**.
% 0.21/0.48  718[5:Rew:706.0,693.0] ||  -> equal(multiply(inverse(sk_c7),sk_c7),sk_c5)**.
% 0.21/0.48  720[5:Rew:33.0,718.0] ||  -> equal(identity,sk_c5)**.
% 0.21/0.48  721[5:Rew:720.0,167.0] ||  -> equal(multiply(u,sk_c5),u)**.
% 0.21/0.48  722[5:Rew:720.0,32.0] ||  -> equal(multiply(sk_c5,u),u)**.
% 0.21/0.48  724[5:Rew:720.0,33.0] ||  -> equal(multiply(inverse(u),u),sk_c5)**.
% 0.21/0.48  740[5:SpR:714.0,65.0] ||  -> equal(multiply(inverse(sk_c1),sk_c7),sk_c7)**.
% 0.21/0.48  742[5:Rew:684.0,740.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c7)**.
% 0.21/0.48  743[5:Rew:709.0,742.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.48  747[5:Rew:743.0,721.0] ||  -> equal(multiply(u,sk_c7),u)**.
% 0.21/0.48  748[5:Rew:743.0,722.0] ||  -> equal(multiply(sk_c7,u),u)**.
% 0.21/0.48  750[5:Rew:743.0,724.0] ||  -> equal(multiply(inverse(u),u),sk_c7)**.
% 0.21/0.48  754[5:Rew:747.0,711.0] || equal(sk_c3,sk_c7)** -> .
% 0.21/0.48  798[5:SpR:430.0,750.0] ||  -> equal(multiply(sk_c7,sk_c3),sk_c7)**.
% 0.21/0.48  800[5:Rew:748.0,798.0] ||  -> equal(sk_c3,sk_c7)**.
% 0.21/0.48  801[5:MRR:800.0,754.0] ||  -> .
% 0.21/0.48  805[4:Spt:801.0,19.0,433.0] || equal(inverse(sk_c4),sk_c6)** -> .
% 0.21/0.48  806[4:Spt:801.0,19.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.48  807[4:MRR:29.0,805.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.48  808[4:MRR:14.0,805.0] ||  -> equal(inverse(sk_c1),sk_c7)**.
% 0.21/0.48  809[4:MRR:24.0,805.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.48  810[4:MRR:9.0,805.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c6)**.
% 0.21/0.48  811[4:MRR:4.0,805.0] ||  -> equal(multiply(sk_c7,sk_c6),sk_c5)**.
% 0.21/0.48  812[4:Rew:811.0,425.7,806.0,425.6] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** equal(sk_c6,sk_c6) equal(sk_c5,sk_c5) -> .
% 0.21/0.48  813[4:Obv:812.7] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** -> .
% 0.21/0.48  817[4:SpR:806.0,65.0] ||  -> equal(multiply(inverse(sk_c7),sk_c6),sk_c5)**.
% 0.21/0.48  827[4:SpR:809.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.48  829[4:Rew:806.0,827.0,807.0,827.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.48  831[4:Rew:829.0,422.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.48  833[4:Rew:829.0,428.0] ||  -> equal(multiply(inverse(sk_c7),sk_c5),sk_c7)**.
% 0.21/0.48  835[4:Rew:829.0,810.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c7)**.
% 0.21/0.48  837[4:Rew:829.0,813.0] || equal(inverse(u),sk_c7) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** -> .
% 0.21/0.48  839[4:Rew:829.0,817.0] ||  -> equal(multiply(inverse(sk_c7),sk_c7),sk_c5)**.
% 0.21/0.48  841[4:Rew:33.0,839.0] ||  -> equal(identity,sk_c5)**.
% 0.21/0.48  843[4:Rew:841.0,167.0] ||  -> equal(multiply(u,sk_c5),u)**.
% 0.21/0.48  846[4:Rew:843.0,833.0] ||  -> equal(inverse(sk_c7),sk_c7)**.
% 0.21/0.48  850[4:Rew:829.0,837.5,829.0,837.4,843.0,837.3,829.0,837.3] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(u,sk_c7) equal(multiply(v,sk_c7),sk_c7)** equal(multiply(w,sk_c7),sk_c7)** -> .
% 0.21/0.48  851[4:Con:850.2] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7) equal(u,sk_c7) equal(multiply(v,sk_c7),sk_c7)** -> .
% 0.21/0.48  864[4:SpR:835.0,65.0] ||  -> equal(multiply(inverse(sk_c1),sk_c7),sk_c7)**.
% 0.21/0.48  866[4:Rew:831.0,864.0,808.0,864.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.48  871[4:Rew:866.0,843.0] ||  -> equal(multiply(u,sk_c7),u)**.
% 0.21/0.48  881[4:Rew:871.0,851.3] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7)** equal(u,sk_c7) equal(v,sk_c7) -> .
% 0.21/0.48  889[4:Con:881.1] || equal(inverse(u),sk_c7)** equal(u,sk_c7) -> .
% 0.21/0.48  953[4:SpL:846.0,889.0] || equal(sk_c7,sk_c7)* equal(sk_c7,sk_c7)* -> .
% 0.21/0.48  955[4:Obv:953.1] ||  -> .
% 0.21/0.48  956[3:Spt:955.0,17.0,430.0] || equal(inverse(sk_c3),sk_c7)** -> .
% 0.21/0.48  957[3:Spt:955.0,17.1] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.48  958[3:MRR:27.0,956.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.48  959[3:MRR:12.0,956.0] ||  -> equal(inverse(sk_c1),sk_c7)**.
% 0.21/0.48  960[3:MRR:22.0,956.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.48  961[3:MRR:7.0,956.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c6)**.
% 0.21/0.48  962[3:MRR:2.0,956.0] ||  -> equal(multiply(sk_c7,sk_c6),sk_c5)**.
% 0.21/0.48  963[3:Rew:962.0,425.7,957.0,425.6] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** equal(sk_c6,sk_c6) equal(sk_c5,sk_c5) -> .
% 0.21/0.48  964[3:Obv:963.7] || equal(inverse(u),sk_c6) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** -> .
% 0.21/0.48  968[3:SpR:957.0,65.0] ||  -> equal(multiply(inverse(sk_c7),sk_c6),sk_c5)**.
% 0.21/0.48  978[3:SpR:960.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.48  980[3:Rew:957.0,978.0,958.0,978.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.48  982[3:Rew:980.0,422.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.48  983[3:Rew:980.0,428.0] ||  -> equal(multiply(inverse(sk_c7),sk_c5),sk_c7)**.
% 0.21/0.48  985[3:Rew:980.0,961.0] ||  -> equal(multiply(sk_c1,sk_c7),sk_c7)**.
% 0.21/0.48  987[3:Rew:980.0,964.0] || equal(inverse(u),sk_c7) equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(multiply(u,sk_c5),sk_c6)** equal(multiply(v,sk_c6),sk_c7)** equal(multiply(w,sk_c7),sk_c6)** -> .
% 0.21/0.48  989[3:Rew:980.0,968.0] ||  -> equal(multiply(inverse(sk_c7),sk_c7),sk_c5)**.
% 0.21/0.48  991[3:Rew:33.0,989.0] ||  -> equal(identity,sk_c5)**.
% 0.21/0.48  992[3:Rew:991.0,167.0] ||  -> equal(multiply(u,sk_c5),u)**.
% 0.21/0.48  996[3:Rew:992.0,983.0] ||  -> equal(inverse(sk_c7),sk_c7)**.
% 0.21/0.48  1000[3:Rew:980.0,987.5,980.0,987.4,992.0,987.3,980.0,987.3] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7) equal(inverse(w),sk_c7) equal(u,sk_c7) equal(multiply(v,sk_c7),sk_c7)** equal(multiply(w,sk_c7),sk_c7)** -> .
% 0.21/0.48  1001[3:Con:1000.2] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7) equal(u,sk_c7) equal(multiply(v,sk_c7),sk_c7)** -> .
% 0.21/0.48  1005[3:SpR:985.0,65.0] ||  -> equal(multiply(inverse(sk_c1),sk_c7),sk_c7)**.
% 0.21/0.48  1007[3:Rew:959.0,1005.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c7)**.
% 0.21/0.48  1008[3:Rew:982.0,1007.0] ||  -> equal(sk_c5,sk_c7)**.
% 0.21/0.48  1012[3:Rew:1008.0,992.0] ||  -> equal(multiply(u,sk_c7),u)**.
% 0.21/0.48  1018[3:Rew:1012.0,1001.3] || equal(inverse(u),sk_c7)** equal(inverse(v),sk_c7)** equal(u,sk_c7) equal(v,sk_c7) -> .
% 0.21/0.48  1030[3:Con:1018.1] || equal(inverse(u),sk_c7)** equal(u,sk_c7) -> .
% 0.21/0.48  1058[3:SpL:996.0,1030.0] || equal(sk_c7,sk_c7)* equal(sk_c7,sk_c7)* -> .
% 0.21/0.48  1059[3:Obv:1058.1] ||  -> .
% 0.21/0.48  1060[2:Spt:1059.0,1.0,422.0] || equal(multiply(sk_c6,sk_c7),sk_c5)** -> .
% 0.21/0.48  1061[2:Spt:1059.0,1.1] ||  -> equal(multiply(sk_c7,sk_c6),sk_c5)**.
% 0.21/0.48  1062[2:MRR:26.1,1060.0] ||  -> equal(inverse(sk_c2),sk_c7)**.
% 0.21/0.48  1064[2:MRR:21.0,1060.0] ||  -> equal(multiply(sk_c2,sk_c7),sk_c5)**.
% 0.21/0.48  1066[2:MRR:16.0,1060.0] ||  -> equal(multiply(sk_c7,sk_c5),sk_c6)**.
% 0.21/0.48  1075[2:SpR:1064.0,65.0] ||  -> equal(multiply(inverse(sk_c2),sk_c5),sk_c7)**.
% 0.21/0.48  1077[2:Rew:1062.0,1075.0] ||  -> equal(multiply(sk_c7,sk_c5),sk_c7)**.
% 0.21/0.48  1078[2:Rew:1066.0,1077.0] ||  -> equal(sk_c6,sk_c7)**.
% 0.21/0.48  1079[2:Rew:1078.0,1061.0] ||  -> equal(multiply(sk_c7,sk_c7),sk_c5)**.
% 0.21/0.48  1080[2:Rew:1078.0,1060.0] || equal(multiply(sk_c7,sk_c7),sk_c5)** -> .
% 0.21/0.48  1085[2:Rew:1079.0,1080.0] || equal(sk_c5,sk_c5)* -> .
% 0.21/0.48  1086[2:Obv:1085.0] ||  -> .
% 0.21/0.48  % SZS output end Refutation
% 0.21/0.48  Formulae used in the proof : prove_this_1 prove_this_2 prove_this_4 prove_this_7 prove_this_8 prove_this_9 prove_this_12 prove_this_13 prove_this_14 prove_this_16 prove_this_17 prove_this_18 prove_this_19 prove_this_20 prove_this_21 prove_this_22 prove_this_23 prove_this_24 prove_this_25 prove_this_26 prove_this_27 prove_this_28 prove_this_29 prove_this_30 prove_this_31 left_identity left_inverse associativity
% 0.21/0.48  
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