let ll1, ll2 be FinSequence of QC-variables ; ( ex k being Element of NAT ex P being QC-pred_symbol of k ex ll being QC-variable_list of k st
( ll1 = ll & F = P ! ll ) & ex k being Element of NAT ex P being QC-pred_symbol of k ex ll being QC-variable_list of k st
( ll2 = ll & F = P ! ll ) implies ll1 = ll2 )
given k1 being Element of NAT , P1 being QC-pred_symbol of k1, ll19 being QC-variable_list of k1 such that A3:
ll1 = ll19
and
A4:
F = P1 ! ll19
; ( for k being Element of NAT
for P being QC-pred_symbol of k
for ll being QC-variable_list of k holds
( not ll2 = ll or not F = P ! ll ) or ll1 = ll2 )
A5:
F = <*P1*> ^ ll19
by A4, Th23;
given k2 being Element of NAT , P2 being QC-pred_symbol of k2, ll29 being QC-variable_list of k2 such that A6:
ll2 = ll29
and
A7:
F = P2 ! ll29
; ll1 = ll2
A8:
F = <*P2*> ^ ll29
by A7, Th23;
P1 =
the_pred_symbol_of F
by A1, A4, Def21
.=
P2
by A1, A7, Def21
;
hence
ll1 = ll2
by A3, A6, A5, A8, FINSEQ_1:46; verum