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Zipperpin---2.1.9999.UNS-Ref.s

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%------------------------------------------------------------------------------
% File     : Zipperpin---2.1.9999
% Problem  : SYO691-1.001 : TPTP v9.2.0. Released v7.3.0.
% Transfm  : none
% Format   : tptp:raw
% Command  : python3 /export/starexec/sandbox/solver/bin/portfolio.lams.parallel.py %s %d /export/starexec/sandbox/tmp/tmp.yFkIVPXCBs true

% Computer : n017.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 Oct  2 05:08:10 PM UTC 2025

% Result   : Unsatisfiable 4.06s 1.19s
% Output   : Refutation 4.06s
% Verified : 
% SZS Type : -

% Comments : 
%------------------------------------------------------------------------------
%----WARNING: Could not form TPTP format derivation
%------------------------------------------------------------------------------
%----ORIGINAL SYSTEM OUTPUT
% 0.05/0.13  % Problem  : SYO691-1.001 : TPTP v9.2.0. Released v7.3.0.
% 0.05/0.14  % Command  : python3 /export/starexec/sandbox/solver/bin/portfolio.lams.parallel.py %s %d /export/starexec/sandbox/tmp/tmp.yFkIVPXCBs true
% 0.13/0.35  % Computer : n017.cluster.edu
% 0.13/0.35  % Model    : x86_64 x86_64
% 0.13/0.35  % CPU      : Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
% 0.13/0.35  % Memory   : 8042.1875MB
% 0.13/0.35  % OS       : Linux 3.10.0-693.el7.x86_64
% 0.13/0.35  % CPULimit : 300
% 0.13/0.35  % WCLimit  : 300
% 0.13/0.35  % DateTime : Wed Oct  1 17:53:38 EDT 2025
% 0.13/0.35  % CPUTime  : 
% 0.13/0.35  % Running portfolio for 300 s
% 0.13/0.35  % File         : /export/starexec/sandbox/benchmark/theBenchmark.p
% 0.13/0.35  % Number of cores: 8
% 0.13/0.36  % Python version: Python 3.6.8
% 0.13/0.36  % Running in FO mode
% 0.56/0.66  % Total configuration time : 435
% 0.56/0.66  % Estimated wc time : 1092
% 0.56/0.66  % Estimated cpu time (7 cpus) : 156.0
% 0.58/0.73  % /export/starexec/sandbox/solver/bin/fo/fo6_bce.sh running for 75s
% 0.58/0.75  % /export/starexec/sandbox/solver/bin/fo/fo3_bce.sh running for 75s
% 0.58/0.77  % /export/starexec/sandbox/solver/bin/fo/fo1_av.sh running for 75s
% 0.58/0.78  % /export/starexec/sandbox/solver/bin/fo/fo7.sh running for 63s
% 0.58/0.78  % /export/starexec/sandbox/solver/bin/fo/fo13.sh running for 50s
% 0.58/0.78  % /export/starexec/sandbox/solver/bin/fo/fo5.sh running for 50s
% 0.58/0.79  % /export/starexec/sandbox/solver/bin/fo/fo4.sh running for 50s
% 4.06/1.19  % Solved by fo/fo13.sh.
% 4.06/1.19  % done 132 iterations in 0.381s
% 4.06/1.19  % SZS status Theorem for '/export/starexec/sandbox/benchmark/theBenchmark.p'
% 4.06/1.19  % SZS output start Refutation
% 4.06/1.19  thf(succ_type, type, succ: $i > $i).
% 4.06/1.19  thf(a_type, type, a: $i).
% 4.06/1.19  thf(f_type, type, f: $i > $i > $i).
% 4.06/1.19  thf(top_type, type, top: $i > $i > $o).
% 4.06/1.19  thf(seq_type, type, seq: $i > $i > $i > $o).
% 4.06/1.19  thf(zero_type, type, zero: $i).
% 4.06/1.19  thf(step_type, type, step: $i > $i > $o).
% 4.06/1.19  thf(rule_1, axiom,
% 4.06/1.19    (top @
% 4.06/1.19     ( f @ ( f @ ( f @ Z @ a ) @ Y ) @ ( f @ X @ a ) ) @ 
% 4.06/1.19     ( f @ ( f @ X @ ( f @ ( f @ Y @ a ) @ a ) ) @ Z ))).
% 4.06/1.19  thf(zip_derived_cl0, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19          (top @ (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ 
% 4.06/1.19           (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0))),
% 4.06/1.19      inference('cnf', [status(esa)], [rule_1])).
% 4.06/1.19  thf(rewrite_top, axiom, (( ~( top @ X @ Y ) ) | ( step @ X @ Y ))).
% 4.06/1.19  thf(zip_derived_cl2, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i]: (~ (top @ X0 @ X1) |  (step @ X0 @ X1))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_top])).
% 4.06/1.19  thf(zip_derived_cl8, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19          (step @ (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ 
% 4.06/1.19           (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl0, zip_derived_cl2])).
% 4.06/1.19  thf(rewrite_left, axiom,
% 4.06/1.19    (( ~( step @ X @ Y ) ) | ( step @ ( f @ X @ Z ) @ ( f @ Y @ Z ) ))).
% 4.06/1.19  thf(zip_derived_cl3, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19         (~ (step @ X0 @ X1) |  (step @ (f @ X0 @ X2) @ (f @ X1 @ X2)))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_left])).
% 4.06/1.19  thf(zip_derived_cl9, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19          (step @ (f @ (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ X3) @ 
% 4.06/1.19           (f @ (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0) @ X3))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl8, zip_derived_cl3])).
% 4.06/1.19  thf(zip_derived_cl3, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19         (~ (step @ X0 @ X1) |  (step @ (f @ X0 @ X2) @ (f @ X1 @ X2)))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_left])).
% 4.06/1.19  thf(zip_derived_cl12, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i]:
% 4.06/1.19          (step @ 
% 4.06/1.19           (f @ (f @ (f @ (f @ (f @ X1 @ a) @ X2) @ (f @ X3 @ a)) @ X0) @ X4) @ 
% 4.06/1.19           (f @ (f @ (f @ (f @ X3 @ (f @ (f @ X2 @ a) @ a)) @ X1) @ X0) @ X4))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl9, zip_derived_cl3])).
% 4.06/1.19  thf(zip_derived_cl3, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19         (~ (step @ X0 @ X1) |  (step @ (f @ X0 @ X2) @ (f @ X1 @ X2)))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_left])).
% 4.06/1.19  thf(zip_derived_cl29, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i, X5 : $i]:
% 4.06/1.19          (step @ 
% 4.06/1.19           (f @ 
% 4.06/1.19            (f @ (f @ (f @ (f @ (f @ X2 @ a) @ X3) @ (f @ X4 @ a)) @ X1) @ X0) @ 
% 4.06/1.19            X5) @ 
% 4.06/1.19           (f @ 
% 4.06/1.19            (f @ (f @ (f @ (f @ X4 @ (f @ (f @ X3 @ a) @ a)) @ X2) @ X1) @ X0) @ 
% 4.06/1.19            X5))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl12, zip_derived_cl3])).
% 4.06/1.19  thf(zip_derived_cl12, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i]:
% 4.06/1.19          (step @ 
% 4.06/1.19           (f @ (f @ (f @ (f @ (f @ X1 @ a) @ X2) @ (f @ X3 @ a)) @ X0) @ X4) @ 
% 4.06/1.19           (f @ (f @ (f @ (f @ X3 @ (f @ (f @ X2 @ a) @ a)) @ X1) @ X0) @ X4))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl9, zip_derived_cl3])).
% 4.06/1.19  thf(zip_derived_cl9, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19          (step @ (f @ (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ X3) @ 
% 4.06/1.19           (f @ (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0) @ X3))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl8, zip_derived_cl3])).
% 4.06/1.19  thf(zip_derived_cl8, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19          (step @ (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ 
% 4.06/1.19           (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl0, zip_derived_cl2])).
% 4.06/1.19  thf(rewrite_sequence_zero, axiom, (seq @ zero @ X @ X)).
% 4.06/1.19  thf(zip_derived_cl5, plain, (![X0 : $i]:  (seq @ zero @ X0 @ X0)),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_sequence_zero])).
% 4.06/1.19  thf(rewrite_sequence_succ, axiom,
% 4.06/1.19    (( ~( seq @ N @ X @ Y ) ) | ( ~( step @ Y @ Z ) ) | 
% 4.06/1.19     ( seq @ ( succ @ N ) @ X @ Z ))).
% 4.06/1.19  thf(zip_derived_cl6, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19         (~ (seq @ X0 @ X1 @ X2)
% 4.06/1.19          | ~ (step @ X2 @ X3)
% 4.06/1.19          |  (seq @ (succ @ X0) @ X1 @ X3))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_sequence_succ])).
% 4.06/1.19  thf(zip_derived_cl7, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i]:
% 4.06/1.19         (~ (step @ X0 @ X1) |  (seq @ (succ @ zero) @ X0 @ X1))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl5, zip_derived_cl6])).
% 4.06/1.19  thf(zip_derived_cl11, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19          (seq @ (succ @ zero) @ 
% 4.06/1.19           (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ 
% 4.06/1.19           (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl8, zip_derived_cl7])).
% 4.06/1.19  thf(zip_derived_cl6, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19         (~ (seq @ X0 @ X1 @ X2)
% 4.06/1.19          | ~ (step @ X2 @ X3)
% 4.06/1.19          |  (seq @ (succ @ X0) @ X1 @ X3))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_sequence_succ])).
% 4.06/1.19  thf(zip_derived_cl15, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19         (~ (step @ (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0) @ X3)
% 4.06/1.19          |  (seq @ (succ @ (succ @ zero)) @ 
% 4.06/1.19              (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ X3))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl11, zip_derived_cl6])).
% 4.06/1.19  thf(zip_derived_cl6, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19         (~ (seq @ X0 @ X1 @ X2)
% 4.06/1.19          | ~ (step @ X2 @ X3)
% 4.06/1.19          |  (seq @ (succ @ X0) @ X1 @ X3))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_sequence_succ])).
% 4.06/1.19  thf(zip_derived_cl16, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i]:
% 4.06/1.19         (~ (step @ (f @ (f @ X1 @ (f @ (f @ X2 @ a) @ a)) @ X3) @ X0)
% 4.06/1.19          | ~ (step @ X0 @ X4)
% 4.06/1.19          |  (seq @ (succ @ (succ @ (succ @ zero))) @ 
% 4.06/1.19              (f @ (f @ (f @ X3 @ a) @ X2) @ (f @ X1 @ a)) @ X4))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl15, zip_derived_cl6])).
% 4.06/1.19  thf(zip_derived_cl17, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i]:
% 4.06/1.19         (~ (step @ 
% 4.06/1.19             (f @ (f @ (f @ (f @ X3 @ a) @ (f @ (f @ X2 @ a) @ a)) @ X1) @ X0) @ 
% 4.06/1.19             X4)
% 4.06/1.19          |  (seq @ (succ @ (succ @ (succ @ zero))) @ 
% 4.06/1.19              (f @ (f @ (f @ X0 @ a) @ X3) @ (f @ (f @ (f @ X1 @ a) @ X2) @ a)) @ 
% 4.06/1.19              X4))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl9, zip_derived_cl16])).
% 4.06/1.19  thf(zip_derived_cl6, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19         (~ (seq @ X0 @ X1 @ X2)
% 4.06/1.19          | ~ (step @ X2 @ X3)
% 4.06/1.19          |  (seq @ (succ @ X0) @ X1 @ X3))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_sequence_succ])).
% 4.06/1.19  thf(zip_derived_cl23, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i, X5 : $i]:
% 4.06/1.19         (~ (step @ 
% 4.06/1.19             (f @ (f @ (f @ (f @ X3 @ a) @ (f @ (f @ X1 @ a) @ a)) @ X2) @ X4) @ 
% 4.06/1.19             X0)
% 4.06/1.19          | ~ (step @ X0 @ X5)
% 4.06/1.19          |  (seq @ (succ @ (succ @ (succ @ (succ @ zero)))) @ 
% 4.06/1.19              (f @ (f @ (f @ X4 @ a) @ X3) @ (f @ (f @ (f @ X2 @ a) @ X1) @ a)) @ 
% 4.06/1.19              X5))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl17, zip_derived_cl6])).
% 4.06/1.19  thf(zip_derived_cl87, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i]:
% 4.06/1.19         (~ (step @ 
% 4.06/1.19             (f @ 
% 4.06/1.19              (f @ (f @ (f @ (f @ X3 @ a) @ (f @ (f @ a @ a) @ a)) @ X2) @ X1) @ 
% 4.06/1.19              X0) @ 
% 4.06/1.19             X4)
% 4.06/1.19          |  (seq @ (succ @ (succ @ (succ @ (succ @ zero)))) @ 
% 4.06/1.19              (f @ (f @ (f @ X0 @ a) @ (f @ X2 @ a)) @ 
% 4.06/1.19               (f @ (f @ (f @ X1 @ a) @ X3) @ a)) @ 
% 4.06/1.19              X4))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl12, zip_derived_cl23])).
% 4.06/1.19  thf(zip_derived_cl6, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19         (~ (seq @ X0 @ X1 @ X2)
% 4.06/1.19          | ~ (step @ X2 @ X3)
% 4.06/1.19          |  (seq @ (succ @ X0) @ X1 @ X3))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_sequence_succ])).
% 4.06/1.19  thf(zip_derived_cl104, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i, X5 : $i]:
% 4.06/1.19         (~ (step @ 
% 4.06/1.19             (f @ 
% 4.06/1.19              (f @ (f @ (f @ (f @ X1 @ a) @ (f @ (f @ a @ a) @ a)) @ X3) @ X2) @ 
% 4.06/1.19              X4) @ 
% 4.06/1.19             X0)
% 4.06/1.19          | ~ (step @ X0 @ X5)
% 4.06/1.19          |  (seq @ (succ @ (succ @ (succ @ (succ @ (succ @ zero))))) @ 
% 4.06/1.19              (f @ (f @ (f @ X4 @ a) @ (f @ X3 @ a)) @ 
% 4.06/1.19               (f @ (f @ (f @ X2 @ a) @ X1) @ a)) @ 
% 4.06/1.19              X5))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl87, zip_derived_cl6])).
% 4.06/1.19  thf(zip_derived_cl448, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i, X4 : $i]:
% 4.06/1.19         (~ (step @ 
% 4.06/1.19             (f @ 
% 4.06/1.19              (f @ 
% 4.06/1.19               (f @ (f @ (f @ (f @ a @ a) @ (f @ (f @ a @ a) @ a)) @ X3) @ X2) @ 
% 4.06/1.19               X1) @ 
% 4.06/1.19              X0) @ 
% 4.06/1.19             X4)
% 4.06/1.19          |  (seq @ (succ @ (succ @ (succ @ (succ @ (succ @ zero))))) @ 
% 4.06/1.19              (f @ (f @ (f @ X0 @ a) @ (f @ X2 @ a)) @ 
% 4.06/1.19               (f @ (f @ (f @ X1 @ a) @ (f @ X3 @ a)) @ a)) @ 
% 4.06/1.19              X4))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl29, zip_derived_cl104])).
% 4.06/1.19  thf(prove, conjecture,
% 4.06/1.19    (seq @ ( succ @ ( succ @ ( succ @ ( succ @ ( succ @ zero ) ) ) ) ) @ X @ X)).
% 4.06/1.19  thf(zf_stmt_0, negated_conjecture,
% 4.06/1.19    (~( seq @
% 4.06/1.19        ( succ @ ( succ @ ( succ @ ( succ @ ( succ @ zero ) ) ) ) ) @ X @ X )),
% 4.06/1.19    inference('cnf.neg', [status(esa)], [prove])).
% 4.06/1.19  thf(zip_derived_cl1, plain,
% 4.06/1.19      (![X0 : $i]:
% 4.06/1.19         ~ (seq @ (succ @ (succ @ (succ @ (succ @ (succ @ zero))))) @ X0 @ X0)),
% 4.06/1.19      inference('cnf', [status(esa)], [zf_stmt_0])).
% 4.06/1.19  thf(zip_derived_cl466, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19         ~ (step @ 
% 4.06/1.19            (f @ 
% 4.06/1.19             (f @ 
% 4.06/1.19              (f @ (f @ (f @ (f @ a @ a) @ (f @ (f @ a @ a) @ a)) @ X0) @ X2) @ 
% 4.06/1.19              X1) @ 
% 4.06/1.19             X3) @ 
% 4.06/1.19            (f @ (f @ (f @ X3 @ a) @ (f @ X2 @ a)) @ 
% 4.06/1.19             (f @ (f @ (f @ X1 @ a) @ (f @ X0 @ a)) @ a)))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl448, zip_derived_cl1])).
% 4.06/1.19  thf(zip_derived_cl8, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19          (step @ (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a)) @ 
% 4.06/1.19           (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl0, zip_derived_cl2])).
% 4.06/1.19  thf(rewrite_right, axiom,
% 4.06/1.19    (( ~( step @ Y @ Z ) ) | ( step @ ( f @ X @ Y ) @ ( f @ X @ Z ) ))).
% 4.06/1.19  thf(zip_derived_cl4, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i]:
% 4.06/1.19         (~ (step @ X0 @ X1) |  (step @ (f @ X2 @ X0) @ (f @ X2 @ X1)))),
% 4.06/1.19      inference('cnf', [status(esa)], [rewrite_right])).
% 4.06/1.19  thf(zip_derived_cl10, plain,
% 4.06/1.19      (![X0 : $i, X1 : $i, X2 : $i, X3 : $i]:
% 4.06/1.19          (step @ (f @ X3 @ (f @ (f @ (f @ X0 @ a) @ X1) @ (f @ X2 @ a))) @ 
% 4.06/1.19           (f @ X3 @ (f @ (f @ X2 @ (f @ (f @ X1 @ a) @ a)) @ X0)))),
% 4.06/1.19      inference('s_sup-', [status(thm)], [zip_derived_cl8, zip_derived_cl4])).
% 4.06/1.19  thf(zip_derived_cl470, plain, ($false),
% 4.06/1.19      inference('s_sup+', [status(thm)], [zip_derived_cl466, zip_derived_cl10])).
% 4.06/1.19  
% 4.06/1.19  % SZS output end Refutation
% 4.06/1.19  
% 4.06/1.19  
% 4.06/1.19  % Terminating...
% 4.54/1.27  % Runner terminated.
% 4.54/1.29  % Zipperpin 1.5 exiting
%------------------------------------------------------------------------------