let H, F be CTL-formula; for sq being FinSequence st H = F ^ sq holds
H = F
let sq be FinSequence; ( H = F ^ sq implies H = F )
defpred S1[ Nat] means for H, F being CTL-formula
for sq being FinSequence st len H = $1 & H = F ^ sq holds
H = F;
for n being Nat st ( for k being Nat st k < n holds
for H, F being CTL-formula
for sq being FinSequence st len H = k & H = F ^ sq holds
H = F ) holds
for H, F being CTL-formula
for sq being FinSequence st len H = n & H = F ^ sq holds
H = F
proof
let n be
Nat;
( ( for k being Nat st k < n holds
for H, F being CTL-formula
for sq being FinSequence st len H = k & H = F ^ sq holds
H = F ) implies for H, F being CTL-formula
for sq being FinSequence st len H = n & H = F ^ sq holds
H = F )
assume A1:
for
k being
Nat st
k < n holds
for
H,
F being
CTL-formula for
sq being
FinSequence st
len H = k &
H = F ^ sq holds
H = F
;
for H, F being CTL-formula
for sq being FinSequence st len H = n & H = F ^ sq holds
H = F
let H,
F be
CTL-formula;
for sq being FinSequence st len H = n & H = F ^ sq holds
H = Flet sq be
FinSequence;
( len H = n & H = F ^ sq implies H = F )
assume that A2:
len H = n
and A3:
H = F ^ sq
;
H = F
A4:
dom F = Seg (len F)
by FINSEQ_1:def 3;
1
<= len F
by Lm10;
then A5:
1
in dom F
by A4, FINSEQ_1:3;
A6:
now A7:
len <*0 *> = 1
by FINSEQ_1:57;
assume A8:
H is
negative
;
H = Fthen consider H1 being
CTL-formula such that A9:
H = 'not' H1
by Def15;
(F ^ sq) . 1
= 0
by A3, A8, Lm3;
then
F . 1
= 0
by A5, FINSEQ_1:def 7;
then
F is
negative
by Lm9;
then consider F1 being
CTL-formula such that A10:
F = 'not' F1
by Def15;
(len <*0 *>) + (len H1) = len H
by A9, FINSEQ_1:35;
then A11:
len H1 < len H
by A7, NAT_1:13;
(<*0 *> ^ F1) ^ sq = <*0 *> ^ (F1 ^ sq)
by FINSEQ_1:45;
then
H1 = F1 ^ sq
by A3, A9, A10, FINSEQ_1:46;
hence
H = F
by A1, A2, A9, A10, A11;
verum end;
A12:
now A13:
len <*4*> = 1
by FINSEQ_1:57;
assume A14:
H is
ExistUntill
;
H = Fthen consider G1,
G being
CTL-formula such that A15:
H = G1 EU G
by Def19;
(F ^ sq) . 1
= 4
by A3, A14, Lm7;
then
F . 1
= 4
by A5, FINSEQ_1:def 7;
then
F is
ExistUntill
by Lm9;
then consider F1,
H1 being
CTL-formula such that A16:
F = F1 EU H1
by Def19;
A17:
(len G) + (1 + (len G1)) = ((len G) + 1) + (len G1)
;
A18:
len (<*4*> ^ G1) = (len <*4*>) + (len G1)
by FINSEQ_1:35;
(len (<*4*> ^ G1)) + (len G) = len H
by A15, FINSEQ_1:35;
then
(len G) + 1
<= len H
by A18, A13, A17, NAT_1:11;
then A19:
len G < len H
by NAT_1:13;
A20:
(F1 ^ H1) ^ sq = F1 ^ (H1 ^ sq)
by FINSEQ_1:45;
A25:
(<*4*> ^ (F1 ^ H1)) ^ sq = <*4*> ^ ((F1 ^ H1) ^ sq)
by FINSEQ_1:45;
A32:
(<*4*> ^ F1) ^ H1 = <*4*> ^ (F1 ^ H1)
by FINSEQ_1:45;
(<*4*> ^ G1) ^ G = <*4*> ^ (G1 ^ G)
by FINSEQ_1:45;
then A33:
G1 ^ G = F1 ^ (H1 ^ sq)
by A3, A15, A16, A32, A25, A20, FINSEQ_1:46;
then
(
len F1 <= len G1 implies ex
sq9 being
FinSequence st
G1 = F1 ^ sq9 )
by FINSEQ_1:64;
then
G = H1 ^ sq
by A33, A21, A26, FINSEQ_1:46, FINSEQ_1:64;
hence
H = F
by A1, A2, A3, A16, A32, A25, A20, A19;
verum end;
A34:
now A35:
len <*1*> = 1
by FINSEQ_1:57;
assume A36:
H is
conjunctive
;
H = Fthen consider G1,
G being
CTL-formula such that A37:
H = G1 '&' G
by Def16;
(F ^ sq) . 1
= 1
by A3, A36, Lm4;
then
F . 1
= 1
by A5, FINSEQ_1:def 7;
then
F is
conjunctive
by Lm9;
then consider F1,
H1 being
CTL-formula such that A38:
F = F1 '&' H1
by Def16;
A39:
(len G) + (1 + (len G1)) = ((len G) + 1) + (len G1)
;
A40:
len (<*1*> ^ G1) = (len <*1*>) + (len G1)
by FINSEQ_1:35;
(len (<*1*> ^ G1)) + (len G) = len H
by A37, FINSEQ_1:35;
then
(len G) + 1
<= len H
by A40, A35, A39, NAT_1:11;
then A41:
len G < len H
by NAT_1:13;
A42:
(F1 ^ H1) ^ sq = F1 ^ (H1 ^ sq)
by FINSEQ_1:45;
A47:
(<*1*> ^ (F1 ^ H1)) ^ sq = <*1*> ^ ((F1 ^ H1) ^ sq)
by FINSEQ_1:45;
A54:
(<*1*> ^ F1) ^ H1 = <*1*> ^ (F1 ^ H1)
by FINSEQ_1:45;
(<*1*> ^ G1) ^ G = <*1*> ^ (G1 ^ G)
by FINSEQ_1:45;
then A55:
G1 ^ G = F1 ^ (H1 ^ sq)
by A3, A37, A38, A54, A47, A42, FINSEQ_1:46;
then
(
len F1 <= len G1 implies ex
sq9 being
FinSequence st
G1 = F1 ^ sq9 )
by FINSEQ_1:64;
then
G = H1 ^ sq
by A55, A43, A48, FINSEQ_1:46, FINSEQ_1:64;
hence
H = F
by A1, A2, A3, A38, A54, A47, A42, A41;
verum end;
A56:
now A57:
len <*3*> = 1
by FINSEQ_1:57;
assume A58:
H is
ExistGlobal
;
H = Fthen consider H1 being
CTL-formula such that A59:
H = EG H1
by Def18;
(F ^ sq) . 1
= 3
by A3, A58, Lm6;
then
F . 1
= 3
by A5, FINSEQ_1:def 7;
then
F is
ExistGlobal
by Lm9;
then consider F1 being
CTL-formula such that A60:
F = EG F1
by Def18;
(len <*3*>) + (len H1) = len H
by A59, FINSEQ_1:35;
then A61:
len H1 < len H
by A57, NAT_1:13;
(<*3*> ^ F1) ^ sq = <*3*> ^ (F1 ^ sq)
by FINSEQ_1:45;
then
H1 = F1 ^ sq
by A3, A59, A60, FINSEQ_1:46;
hence
H = F
by A1, A2, A59, A60, A61;
verum end;
A62:
now A63:
len <*2*> = 1
by FINSEQ_1:57;
assume A64:
H is
ExistNext
;
H = Fthen consider H1 being
CTL-formula such that A65:
H = EX H1
by Def17;
(F ^ sq) . 1
= 2
by A3, A64, Lm5;
then
F . 1
= 2
by A5, FINSEQ_1:def 7;
then
F is
ExistNext
by Lm9;
then consider F1 being
CTL-formula such that A66:
F = EX F1
by Def17;
(len <*2*>) + (len H1) = len H
by A65, FINSEQ_1:35;
then A67:
len H1 < len H
by A63, NAT_1:13;
(<*2*> ^ F1) ^ sq = <*2*> ^ (F1 ^ sq)
by FINSEQ_1:45;
then
H1 = F1 ^ sq
by A3, A65, A66, FINSEQ_1:46;
hence
H = F
by A1, A2, A65, A66, A67;
verum end;
A68:
(len F) + (len sq) = len (F ^ sq)
by FINSEQ_1:35;
hence
H = F
by A6, A34, A62, A56, A12, Th2;
verum
end;
then A71:
for k being Nat st ( for n being Nat st n < k holds
S1[n] ) holds
S1[k]
;
A72:
for n being Nat holds S1[n]
from NAT_1:sch 4(A71);
len H = len H
;
hence
( H = F ^ sq implies H = F )
by A72; verum