:: SPRECT_2 semantic presentation

theorem Th1: :: SPRECT_2:1
for b1, b2, b3, b4 being set st b1 /\ b2 c= {b4} & b4 in b3 & b3 misses b2 holds
b1 \/ b3 misses b2
proof end;

theorem Th2: :: SPRECT_2:2
for b1, b2, b3, b4 being set st b1 /\ b3 = {b4} & b4 in b2 & b2 c= b3 holds
b1 /\ b2 = {b4}
proof end;

theorem Th3: :: SPRECT_2:3
canceled;

theorem Th4: :: SPRECT_2:4
for b1, b2 being set st ( for b3, b4 being set st b3 in b1 & b4 in b2 holds
b3 misses b4 ) holds
union b1 misses union b2
proof end;

theorem Th5: :: SPRECT_2:5
for b1, b2, b3 being Nat
for b4 being non empty set
for b5 being FinSequence of b4 st b1 <= b2 & b1 in dom b5 & b2 in dom b5 & b3 in dom (mid b5,b1,b2) holds
(b3 + b1) -' 1 in dom b5
proof end;

theorem Th6: :: SPRECT_2:6
for b1, b2, b3 being Nat
for b4 being non empty set
for b5 being FinSequence of b4 st b1 > b2 & b1 in dom b5 & b2 in dom b5 & b3 in dom (mid b5,b1,b2) holds
(b1 -' b3) + 1 in dom b5
proof end;

theorem Th7: :: SPRECT_2:7
for b1, b2, b3 being Nat
for b4 being non empty set
for b5 being FinSequence of b4 st b1 <= b2 & b1 in dom b5 & b2 in dom b5 & b3 in dom (mid b5,b1,b2) holds
(mid b5,b1,b2) /. b3 = b5 /. ((b3 + b1) -' 1)
proof end;

theorem Th8: :: SPRECT_2:8
for b1, b2, b3 being Nat
for b4 being non empty set
for b5 being FinSequence of b4 st b1 > b2 & b1 in dom b5 & b2 in dom b5 & b3 in dom (mid b5,b1,b2) holds
(mid b5,b1,b2) /. b3 = b5 /. ((b1 -' b3) + 1)
proof end;

theorem Th9: :: SPRECT_2:9
for b1, b2 being Nat
for b3 being non empty set
for b4 being FinSequence of b3 st b1 in dom b4 & b2 in dom b4 holds
len (mid b4,b1,b2) >= 1
proof end;

theorem Th10: :: SPRECT_2:10
for b1, b2 being Nat
for b3 being non empty set
for b4 being FinSequence of b3 st b1 in dom b4 & b2 in dom b4 & len (mid b4,b1,b2) = 1 holds
b1 = b2
proof end;

theorem Th11: :: SPRECT_2:11
for b1, b2 being Nat
for b3 being non empty set
for b4 being FinSequence of b3 st b1 in dom b4 & b2 in dom b4 holds
not mid b4,b1,b2 is empty
proof end;

theorem Th12: :: SPRECT_2:12
for b1, b2 being Nat
for b3 being non empty set
for b4 being FinSequence of b3 st b1 in dom b4 & b2 in dom b4 holds
(mid b4,b1,b2) /. 1 = b4 /. b1
proof end;

theorem Th13: :: SPRECT_2:13
for b1, b2 being Nat
for b3 being non empty set
for b4 being FinSequence of b3 st b1 in dom b4 & b2 in dom b4 holds
(mid b4,b1,b2) /. (len (mid b4,b1,b2)) = b4 /. b2
proof end;

theorem Th14: :: SPRECT_2:14
for b1 being compact Subset of (TOP-REAL 2)
for b2 being Point of (TOP-REAL 2) st b2 in b1 & b2 `2 = N-bound b1 holds
b2 in N-most b1
proof end;

theorem Th15: :: SPRECT_2:15
for b1 being compact Subset of (TOP-REAL 2)
for b2 being Point of (TOP-REAL 2) st b2 in b1 & b2 `2 = S-bound b1 holds
b2 in S-most b1
proof end;

theorem Th16: :: SPRECT_2:16
for b1 being compact Subset of (TOP-REAL 2)
for b2 being Point of (TOP-REAL 2) st b2 in b1 & b2 `1 = W-bound b1 holds
b2 in W-most b1
proof end;

theorem Th17: :: SPRECT_2:17
for b1 being compact Subset of (TOP-REAL 2)
for b2 being Point of (TOP-REAL 2) st b2 in b1 & b2 `1 = E-bound b1 holds
b2 in E-most b1
proof end;

theorem Th18: :: SPRECT_2:18
for b1, b2 being Nat
for b3 being FinSequence of (TOP-REAL 2) st 1 <= b1 & b1 <= b2 & b2 <= len b3 holds
L~ (mid b3,b1,b2) = union { (LSeg b3,b4) where B is Nat : ( b1 <= b4 & b4 < b2 ) }
proof end;

theorem Th19: :: SPRECT_2:19
for b1 being FinSequence of (TOP-REAL 2) holds dom (X_axis b1) = dom b1
proof end;

theorem Th20: :: SPRECT_2:20
for b1 being FinSequence of (TOP-REAL 2) holds dom (Y_axis b1) = dom b1
proof end;

theorem Th21: :: SPRECT_2:21
for b1, b2, b3 being Point of (TOP-REAL 2) st b2 in LSeg b1,b3 & b1 `1 <= b2 `1 & b3 `1 <= b2 `1 & not b1 = b2 & not b2 = b3 holds
( b1 `1 = b2 `1 & b3 `1 = b2 `1 )
proof end;

theorem Th22: :: SPRECT_2:22
for b1, b2, b3 being Point of (TOP-REAL 2) st b2 in LSeg b1,b3 & b1 `2 <= b2 `2 & b3 `2 <= b2 `2 & not b1 = b2 & not b2 = b3 holds
( b1 `2 = b2 `2 & b3 `2 = b2 `2 )
proof end;

theorem Th23: :: SPRECT_2:23
for b1, b2, b3 being Point of (TOP-REAL 2) st b2 in LSeg b1,b3 & b1 `1 >= b2 `1 & b3 `1 >= b2 `1 & not b1 = b2 & not b2 = b3 holds
( b1 `1 = b2 `1 & b3 `1 = b2 `1 )
proof end;

theorem Th24: :: SPRECT_2:24
for b1, b2, b3 being Point of (TOP-REAL 2) st b2 in LSeg b1,b3 & b1 `2 >= b2 `2 & b3 `2 >= b2 `2 & not b1 = b2 & not b2 = b3 holds
( b1 `2 = b2 `2 & b3 `2 = b2 `2 )
proof end;

definition
let c1, c2 be FinSequence of (TOP-REAL 2);
pred c2 is_in_the_area_of c1 means :Def1: :: SPRECT_2:def 1
for b1 being Nat st b1 in dom a2 holds
( W-bound (L~ a1) <= (a2 /. b1) `1 & (a2 /. b1) `1 <= E-bound (L~ a1) & S-bound (L~ a1) <= (a2 /. b1) `2 & (a2 /. b1) `2 <= N-bound (L~ a1) );
end;

:: deftheorem Def1 defines is_in_the_area_of SPRECT_2:def 1 :
for b1, b2 being FinSequence of (TOP-REAL 2) holds
( b2 is_in_the_area_of b1 iff for b3 being Nat st b3 in dom b2 holds
( W-bound (L~ b1) <= (b2 /. b3) `1 & (b2 /. b3) `1 <= E-bound (L~ b1) & S-bound (L~ b1) <= (b2 /. b3) `2 & (b2 /. b3) `2 <= N-bound (L~ b1) ) );

theorem Th25: :: SPRECT_2:25
for b1 being non trivial FinSequence of (TOP-REAL 2) holds b1 is_in_the_area_of b1
proof end;

theorem Th26: :: SPRECT_2:26
for b1, b2 being FinSequence of (TOP-REAL 2) st b2 is_in_the_area_of b1 holds
for b3, b4 being Nat st b3 in dom b2 & b4 in dom b2 holds
mid b2,b3,b4 is_in_the_area_of b1
proof end;

theorem Th27: :: SPRECT_2:27
for b1 being non trivial FinSequence of (TOP-REAL 2)
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 holds
mid b1,b2,b3 is_in_the_area_of b1
proof end;

theorem Th28: :: SPRECT_2:28
for b1, b2, b3 being FinSequence of (TOP-REAL 2) st b2 is_in_the_area_of b1 & b3 is_in_the_area_of b1 holds
b2 ^ b3 is_in_the_area_of b1
proof end;

theorem Th29: :: SPRECT_2:29
for b1 being non trivial FinSequence of (TOP-REAL 2) holds <*(NE-corner (L~ b1))*> is_in_the_area_of b1
proof end;

theorem Th30: :: SPRECT_2:30
for b1 being non trivial FinSequence of (TOP-REAL 2) holds <*(NW-corner (L~ b1))*> is_in_the_area_of b1
proof end;

theorem Th31: :: SPRECT_2:31
for b1 being non trivial FinSequence of (TOP-REAL 2) holds <*(SE-corner (L~ b1))*> is_in_the_area_of b1
proof end;

theorem Th32: :: SPRECT_2:32
for b1 being non trivial FinSequence of (TOP-REAL 2) holds <*(SW-corner (L~ b1))*> is_in_the_area_of b1
proof end;

definition
let c1, c2 be FinSequence of (TOP-REAL 2);
pred c2 is_a_h.c._for c1 means :Def2: :: SPRECT_2:def 2
( a2 is_in_the_area_of a1 & (a2 /. 1) `1 = W-bound (L~ a1) & (a2 /. (len a2)) `1 = E-bound (L~ a1) );
pred c2 is_a_v.c._for c1 means :Def3: :: SPRECT_2:def 3
( a2 is_in_the_area_of a1 & (a2 /. 1) `2 = S-bound (L~ a1) & (a2 /. (len a2)) `2 = N-bound (L~ a1) );
end;

:: deftheorem Def2 defines is_a_h.c._for SPRECT_2:def 2 :
for b1, b2 being FinSequence of (TOP-REAL 2) holds
( b2 is_a_h.c._for b1 iff ( b2 is_in_the_area_of b1 & (b2 /. 1) `1 = W-bound (L~ b1) & (b2 /. (len b2)) `1 = E-bound (L~ b1) ) );

:: deftheorem Def3 defines is_a_v.c._for SPRECT_2:def 3 :
for b1, b2 being FinSequence of (TOP-REAL 2) holds
( b2 is_a_v.c._for b1 iff ( b2 is_in_the_area_of b1 & (b2 /. 1) `2 = S-bound (L~ b1) & (b2 /. (len b2)) `2 = N-bound (L~ b1) ) );

theorem Th33: :: SPRECT_2:33
for b1 being FinSequence of (TOP-REAL 2)
for b2, b3 being one-to-one special FinSequence of (TOP-REAL 2) st 2 <= len b2 & 2 <= len b3 & b2 is_a_h.c._for b1 & b3 is_a_v.c._for b1 holds
L~ b2 meets L~ b3
proof end;

definition
let c1 be FinSequence of (TOP-REAL 2);
attr a1 is clockwise_oriented means :Def4: :: SPRECT_2:def 4
(Rotate a1,(N-min (L~ a1))) /. 2 in N-most (L~ a1);
end;

:: deftheorem Def4 defines clockwise_oriented SPRECT_2:def 4 :
for b1 being FinSequence of (TOP-REAL 2) holds
( b1 is clockwise_oriented iff (Rotate b1,(N-min (L~ b1))) /. 2 in N-most (L~ b1) );

theorem Th34: :: SPRECT_2:34
for b1 being standard non constant special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
( b1 is clockwise_oriented iff b1 /. 2 in N-most (L~ b1) )
proof end;

registration
cluster R^2-unit_square -> compact ;
coherence
R^2-unit_square is compact
by TOPREAL2:2;
end;

theorem Th35: :: SPRECT_2:35
N-bound R^2-unit_square = 1
proof end;

theorem Th36: :: SPRECT_2:36
W-bound R^2-unit_square = 0
proof end;

theorem Th37: :: SPRECT_2:37
E-bound R^2-unit_square = 1
proof end;

theorem Th38: :: SPRECT_2:38
S-bound R^2-unit_square = 0
proof end;

Lemma41: NW-corner R^2-unit_square = |[0,1]|
by Th35, Th36, PSCOMP_1:def 35;

Lemma42: NE-corner R^2-unit_square = |[1,1]|
by Th35, Th37, PSCOMP_1:def 36;

theorem Th39: :: SPRECT_2:39
N-most R^2-unit_square = LSeg |[0,1]|,|[1,1]|
proof end;

theorem Th40: :: SPRECT_2:40
N-min R^2-unit_square = |[0,1]|
proof end;

registration
let c1 be non empty non horizontal non vertical compact Subset of (TOP-REAL 2);
cluster SpStSeq a1 -> clockwise_oriented ;
coherence
SpStSeq c1 is clockwise_oriented
proof end;
end;

registration
cluster standard non constant clockwise_oriented FinSequence of the carrier of (TOP-REAL 2);
existence
ex b1 being standard non constant special_circular_sequence st b1 is clockwise_oriented
proof end;
end;

theorem Th41: :: SPRECT_2:41
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 > b3 & ( ( 1 < b3 & b2 <= len b1 ) or ( 1 <= b3 & b2 < len b1 ) ) holds
mid b1,b2,b3 is S-Sequence_in_R2
proof end;

theorem Th42: :: SPRECT_2:42
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 < b3 & ( ( 1 < b2 & b3 <= len b1 ) or ( 1 <= b2 & b3 < len b1 ) ) holds
mid b1,b2,b3 is S-Sequence_in_R2
proof end;

theorem Th43: :: SPRECT_2:43
for b1 being non trivial FinSequence of (TOP-REAL 2) holds N-min (L~ b1) in rng b1
proof end;

theorem Th44: :: SPRECT_2:44
for b1 being non trivial FinSequence of (TOP-REAL 2) holds N-max (L~ b1) in rng b1
proof end;

theorem Th45: :: SPRECT_2:45
for b1 being non trivial FinSequence of (TOP-REAL 2) holds S-min (L~ b1) in rng b1
proof end;

theorem Th46: :: SPRECT_2:46
for b1 being non trivial FinSequence of (TOP-REAL 2) holds S-max (L~ b1) in rng b1
proof end;

theorem Th47: :: SPRECT_2:47
for b1 being non trivial FinSequence of (TOP-REAL 2) holds W-min (L~ b1) in rng b1
proof end;

theorem Th48: :: SPRECT_2:48
for b1 being non trivial FinSequence of (TOP-REAL 2) holds W-max (L~ b1) in rng b1
proof end;

theorem Th49: :: SPRECT_2:49
for b1 being non trivial FinSequence of (TOP-REAL 2) holds E-min (L~ b1) in rng b1
proof end;

theorem Th50: :: SPRECT_2:50
for b1 being non trivial FinSequence of (TOP-REAL 2) holds E-max (L~ b1) in rng b1
proof end;

theorem Th51: :: SPRECT_2:51
for b1, b2, b3, b4 being Nat
for b5 being standard non constant special_circular_sequence st 1 <= b1 & b1 <= b2 & b2 < b3 & b3 <= b4 & b4 <= len b5 & ( 1 < b1 or b4 < len b5 ) holds
L~ (mid b5,b1,b2) misses L~ (mid b5,b3,b4)
proof end;

theorem Th52: :: SPRECT_2:52
for b1, b2, b3, b4 being Nat
for b5 being standard non constant special_circular_sequence st 1 <= b1 & b1 <= b2 & b2 < b3 & b3 <= b4 & b4 <= len b5 & ( 1 < b1 or b4 < len b5 ) holds
L~ (mid b5,b1,b2) misses L~ (mid b5,b4,b3)
proof end;

theorem Th53: :: SPRECT_2:53
for b1, b2, b3, b4 being Nat
for b5 being standard non constant special_circular_sequence st 1 <= b1 & b1 <= b2 & b2 < b3 & b3 <= b4 & b4 <= len b5 & ( 1 < b1 or b4 < len b5 ) holds
L~ (mid b5,b2,b1) misses L~ (mid b5,b4,b3)
proof end;

theorem Th54: :: SPRECT_2:54
for b1, b2, b3, b4 being Nat
for b5 being standard non constant special_circular_sequence st 1 <= b1 & b1 <= b2 & b2 < b3 & b3 <= b4 & b4 <= len b5 & ( 1 < b1 or b4 < len b5 ) holds
L~ (mid b5,b2,b1) misses L~ (mid b5,b3,b4)
proof end;

theorem Th55: :: SPRECT_2:55
for b1 being standard non constant special_circular_sequence holds (N-min (L~ b1)) `1 < (N-max (L~ b1)) `1
proof end;

theorem Th56: :: SPRECT_2:56
for b1 being standard non constant special_circular_sequence holds N-min (L~ b1) <> N-max (L~ b1)
proof end;

theorem Th57: :: SPRECT_2:57
for b1 being standard non constant special_circular_sequence holds (E-min (L~ b1)) `2 < (E-max (L~ b1)) `2
proof end;

theorem Th58: :: SPRECT_2:58
for b1 being standard non constant special_circular_sequence holds E-min (L~ b1) <> E-max (L~ b1)
proof end;

theorem Th59: :: SPRECT_2:59
for b1 being standard non constant special_circular_sequence holds (S-min (L~ b1)) `1 < (S-max (L~ b1)) `1
proof end;

theorem Th60: :: SPRECT_2:60
for b1 being standard non constant special_circular_sequence holds S-min (L~ b1) <> S-max (L~ b1)
proof end;

theorem Th61: :: SPRECT_2:61
for b1 being standard non constant special_circular_sequence holds (W-min (L~ b1)) `2 < (W-max (L~ b1)) `2
proof end;

theorem Th62: :: SPRECT_2:62
for b1 being standard non constant special_circular_sequence holds W-min (L~ b1) <> W-max (L~ b1)
proof end;

theorem Th63: :: SPRECT_2:63
for b1 being standard non constant special_circular_sequence holds LSeg (NW-corner (L~ b1)),(N-min (L~ b1)) misses LSeg (N-max (L~ b1)),(NE-corner (L~ b1))
proof end;

theorem Th64: :: SPRECT_2:64
for b1 being FinSequence of (TOP-REAL 2)
for b2 being Point of (TOP-REAL 2) st b1 is_S-Seq & b2 <> b1 /. 1 & ( b2 `1 = (b1 /. 1) `1 or b2 `2 = (b1 /. 1) `2 ) & (LSeg b2,(b1 /. 1)) /\ (L~ b1) = {(b1 /. 1)} holds
<*b2*> ^ b1 is S-Sequence_in_R2
proof end;

theorem Th65: :: SPRECT_2:65
for b1 being FinSequence of (TOP-REAL 2)
for b2 being Point of (TOP-REAL 2) st b1 is_S-Seq & b2 <> b1 /. (len b1) & ( b2 `1 = (b1 /. (len b1)) `1 or b2 `2 = (b1 /. (len b1)) `2 ) & (LSeg b2,(b1 /. (len b1))) /\ (L~ b1) = {(b1 /. (len b1))} holds
b1 ^ <*b2*> is S-Sequence_in_R2
proof end;

theorem Th66: :: SPRECT_2:66
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b3 = N-max (L~ b1) & N-max (L~ b1) <> NE-corner (L~ b1) holds
(mid b1,b2,b3) ^ <*(NE-corner (L~ b1))*> is S-Sequence_in_R2
proof end;

theorem Th67: :: SPRECT_2:67
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b3 = E-max (L~ b1) & E-max (L~ b1) <> NE-corner (L~ b1) holds
(mid b1,b2,b3) ^ <*(NE-corner (L~ b1))*> is S-Sequence_in_R2
proof end;

theorem Th68: :: SPRECT_2:68
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b3 = S-max (L~ b1) & S-max (L~ b1) <> SE-corner (L~ b1) holds
(mid b1,b2,b3) ^ <*(SE-corner (L~ b1))*> is S-Sequence_in_R2
proof end;

theorem Th69: :: SPRECT_2:69
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b3 = E-max (L~ b1) & E-max (L~ b1) <> NE-corner (L~ b1) holds
(mid b1,b2,b3) ^ <*(NE-corner (L~ b1))*> is S-Sequence_in_R2
proof end;

theorem Th70: :: SPRECT_2:70
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b2 = N-min (L~ b1) & N-min (L~ b1) <> NW-corner (L~ b1) holds
<*(NW-corner (L~ b1))*> ^ (mid b1,b2,b3) is S-Sequence_in_R2
proof end;

theorem Th71: :: SPRECT_2:71
for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b2 = W-min (L~ b1) & W-min (L~ b1) <> SW-corner (L~ b1) holds
<*(SW-corner (L~ b1))*> ^ (mid b1,b2,b3) is S-Sequence_in_R2
proof end;

Lemma73: for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b2 = N-min (L~ b1) & N-min (L~ b1) <> NW-corner (L~ b1) & b1 /. b3 = N-max (L~ b1) & N-max (L~ b1) <> NE-corner (L~ b1) holds
(<*(NW-corner (L~ b1))*> ^ (mid b1,b2,b3)) ^ <*(NE-corner (L~ b1))*> is S-Sequence_in_R2
proof end;

registration
let c1 be standard non constant special_circular_sequence;
cluster L~ a1 -> being_simple_closed_curve ;
coherence
L~ c1 is being_simple_closed_curve
by JORDAN4:63;
end;

Lemma74: for b1 being standard non constant special_circular_sequence holds LSeg (S-max (L~ b1)),(SE-corner (L~ b1)) misses LSeg (NW-corner (L~ b1)),(N-min (L~ b1))
proof end;

Lemma75: for b1 being standard non constant special_circular_sequence
for b2, b3 being Nat st b2 in dom b1 & b3 in dom b1 & mid b1,b2,b3 is S-Sequence_in_R2 & b1 /. b2 = N-min (L~ b1) & N-min (L~ b1) <> NW-corner (L~ b1) & b1 /. b3 = S-max (L~ b1) & S-max (L~ b1) <> SE-corner (L~ b1) holds
(<*(NW-corner (L~ b1))*> ^ (mid b1,b2,b3)) ^ <*(SE-corner (L~ b1))*> is S-Sequence_in_R2
proof end;

theorem Th72: :: SPRECT_2:72
for b1 being standard non constant special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(N-min (L~ b1)) .. b1 < (N-max (L~ b1)) .. b1
proof end;

theorem Th73: :: SPRECT_2:73
for b1 being standard non constant special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(N-max (L~ b1)) .. b1 > 1
proof end;

Lemma77: for b1 being standard non constant special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(N-min (L~ b1)) .. b1 < (E-max (L~ b1)) .. b1
proof end;

Lemma78: for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(N-max (L~ b1)) .. b1 < (S-max (L~ b1)) .. b1
proof end;

Lemma79: for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(N-max (L~ b1)) .. b1 < (S-min (L~ b1)) .. b1
proof end;

theorem Th74: :: SPRECT_2:74
for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) & N-max (L~ b1) <> E-max (L~ b1) holds
(N-max (L~ b1)) .. b1 < (E-max (L~ b1)) .. b1
proof end;

Lemma80: for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(E-max (L~ b1)) .. b1 < (S-max (L~ b1)) .. b1
proof end;

Lemma81: for b1 being standard non constant special_circular_sequence holds (LSeg (N-min (L~ b1)),(NW-corner (L~ b1))) /\ (LSeg (NE-corner (L~ b1)),(E-max (L~ b1))) = {}
proof end;

theorem Th75: :: SPRECT_2:75
for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(E-max (L~ b1)) .. b1 < (E-min (L~ b1)) .. b1
proof end;

theorem Th76: :: SPRECT_2:76
for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) & E-min (L~ b1) <> S-max (L~ b1) holds
(E-min (L~ b1)) .. b1 < (S-max (L~ b1)) .. b1
proof end;

theorem Th77: :: SPRECT_2:77
for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(S-max (L~ b1)) .. b1 < (S-min (L~ b1)) .. b1
proof end;

Lemma84: for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(E-min (L~ b1)) .. b1 < (S-min (L~ b1)) .. b1
proof end;

Lemma85: for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) & N-min (L~ b1) <> W-max (L~ b1) holds
(E-min (L~ b1)) .. b1 < (W-max (L~ b1)) .. b1
proof end;

Lemma86: for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(E-min (L~ b1)) .. b1 < (W-min (L~ b1)) .. b1
proof end;

theorem Th78: :: SPRECT_2:78
for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) & S-min (L~ b1) <> W-min (L~ b1) holds
(S-min (L~ b1)) .. b1 < (W-min (L~ b1)) .. b1
proof end;

theorem Th79: :: SPRECT_2:79
for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) & N-min (L~ b1) <> W-max (L~ b1) holds
(W-min (L~ b1)) .. b1 < (W-max (L~ b1)) .. b1
proof end;

theorem Th80: :: SPRECT_2:80
for b1 being standard non constant clockwise_oriented special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(W-min (L~ b1)) .. b1 < len b1
proof end;

theorem Th81: :: SPRECT_2:81
for b1 being standard non constant special_circular_sequence st b1 /. 1 = N-min (L~ b1) holds
(W-max (L~ b1)) .. b1 < len b1
proof end;