:: Countable Sets and Hessenberg's Theorem
:: by Grzegorz Bancerek
::
:: Received September 5, 1990
:: Copyright (c) 1990-2011 Association of Mizar Users


begin

theorem :: CARD_4:1
canceled;

theorem :: CARD_4:2
canceled;

theorem :: CARD_4:3
canceled;

theorem :: CARD_4:4
canceled;

theorem :: CARD_4:5
canceled;

theorem :: CARD_4:6
canceled;

theorem :: CARD_4:7
canceled;

theorem :: CARD_4:8
canceled;

theorem :: CARD_4:9
canceled;

theorem :: CARD_4:10
canceled;

theorem :: CARD_4:11
canceled;

theorem :: CARD_4:12
canceled;

theorem :: CARD_4:13
canceled;

theorem :: CARD_4:14
canceled;

theorem :: CARD_4:15
canceled;

theorem :: CARD_4:16
canceled;

theorem :: CARD_4:17
canceled;

theorem :: CARD_4:18
canceled;

theorem :: CARD_4:19
canceled;

theorem :: CARD_4:20
canceled;

theorem :: CARD_4:21
canceled;

theorem :: CARD_4:22
canceled;

theorem :: CARD_4:23
canceled;

theorem :: CARD_4:24
canceled;

theorem :: CARD_4:25
canceled;

theorem :: CARD_4:26
canceled;

theorem :: CARD_4:27
canceled;

theorem :: CARD_4:28
canceled;

theorem :: CARD_4:29
canceled;

theorem :: CARD_4:30
canceled;

theorem :: CARD_4:31
canceled;

theorem :: CARD_4:32
canceled;

theorem :: CARD_4:33
canceled;

theorem :: CARD_4:34
canceled;

theorem :: CARD_4:35
canceled;

theorem :: CARD_4:36
canceled;

theorem :: CARD_4:37
canceled;

theorem :: CARD_4:38
canceled;

theorem :: CARD_4:39
canceled;

theorem :: CARD_4:40
canceled;

theorem :: CARD_4:41
canceled;

theorem :: CARD_4:42
canceled;

theorem :: CARD_4:43
for X being set st X is finite holds
X is countable ;

theorem :: CARD_4:44
omega is countable ;

theorem :: CARD_4:45
canceled;

theorem :: CARD_4:46
canceled;

theorem :: CARD_4:47
canceled;

theorem :: CARD_4:48
canceled;

theorem :: CARD_4:49
canceled;

theorem :: CARD_4:50
canceled;

theorem Th51: :: CARD_4:51
for n being Nat
for r being Real holds
( ( r <> 0 or n = 0 ) iff r |^ n <> 0 )
proof end;

Lm1: for n1, m1, n2, m2 being Nat st (2 |^ n1) * ((2 * m1) + 1) = (2 |^ n2) * ((2 * m2) + 1) holds
n1 <= n2
proof end;

theorem Th52: :: CARD_4:52
for n1, m1, n2, m2 being Nat st (2 |^ n1) * ((2 * m1) + 1) = (2 |^ n2) * ((2 * m2) + 1) holds
( n1 = n2 & m1 = m2 )
proof end;

Lm2: for x being set st x in [:NAT,NAT:] holds
ex n1, n2 being Element of NAT st x = [n1,n2]
proof end;

theorem Th53: :: CARD_4:53
( [:NAT,NAT:], NAT are_equipotent & card NAT = card [:NAT,NAT:] )
proof end;

theorem Th54: :: CARD_4:54
omega *` omega = omega by Th53, CARD_1:84, CARD_2:def 2;

theorem Th55: :: CARD_4:55
for X, Y being set st X is countable & Y is countable holds
[:X,Y:] is countable
proof end;

theorem Th56: :: CARD_4:56
for D being non empty set holds
( 1 -tuples_on D,D are_equipotent & card (1 -tuples_on D) = card D )
proof end;

theorem Th57: :: CARD_4:57
for D being non empty set
for n, m being Element of NAT holds
( [:(n -tuples_on D),(m -tuples_on D):],(n + m) -tuples_on D are_equipotent & card [:(n -tuples_on D),(m -tuples_on D):] = card ((n + m) -tuples_on D) )
proof end;

theorem Th58: :: CARD_4:58
for D being non empty set
for n being Element of NAT st D is countable holds
n -tuples_on D is countable
proof end;

theorem :: CARD_4:59
canceled;

theorem :: CARD_4:60
canceled;

theorem Th61: :: CARD_4:61
for f being Function st dom f is countable & ( for x being set st x in dom f holds
f . x is countable ) holds
Union f is countable
proof end;

theorem :: CARD_4:62
for X being set st X is countable & ( for Y being set st Y in X holds
Y is countable ) holds
union X is countable
proof end;

theorem :: CARD_4:63
canceled;

theorem :: CARD_4:64
canceled;

theorem :: CARD_4:65
for D being non empty set st D is countable holds
D * is countable
proof end;

theorem :: CARD_4:66
for D being non empty set holds omega c= card (D *)
proof end;

scheme :: CARD_4:sch 1
FraenCoun1{ F1( set ) -> set , P1[ set ] } :
{ F1(n) where n is Element of NAT : P1[n] } is countable
proof end;

scheme :: CARD_4:sch 2
FraenCoun2{ F1( set , set ) -> set , P1[ set , set ] } :
{ F1(n1,n2) where n1, n2 is Element of NAT : P1[n1,n2] } is countable
proof end;

scheme :: CARD_4:sch 3
FraenCoun3{ F1( set , set , set ) -> set , P1[ set , set , set ] } :
{ F1(n1,n2,n3) where n1, n2, n3 is Element of NAT : P1[n1,n2,n3] } is countable
proof end;

theorem :: CARD_4:67
canceled;

theorem :: CARD_4:68
canceled;

theorem :: CARD_4:69
canceled;

theorem :: CARD_4:70
canceled;

theorem :: CARD_4:71
canceled;

theorem :: CARD_4:72
canceled;

theorem :: CARD_4:73
canceled;

theorem :: CARD_4:74
canceled;

theorem :: CARD_4:75
canceled;

theorem :: CARD_4:76
canceled;

theorem Th77: :: CARD_4:77
for M being Cardinal st not M is finite holds
M *` M = M
proof end;

theorem Th78: :: CARD_4:78
for M, N being Cardinal st not M is finite & 0 in N & ( N c= M or N in M ) holds
( M *` N = M & N *` M = M )
proof end;

theorem Th79: :: CARD_4:79
for M, N being Cardinal st not M is finite & ( N c= M or N in M ) holds
( M *` N c= M & N *` M c= M )
proof end;

theorem :: CARD_4:80
for X being set st not X is finite holds
( [:X,X:],X are_equipotent & card [:X,X:] = card X )
proof end;

theorem :: CARD_4:81
for X, Y being set st not X is finite & Y is finite & Y <> {} holds
( [:X,Y:],X are_equipotent & card [:X,Y:] = card X )
proof end;

theorem :: CARD_4:82
for K, L, M, N being Cardinal st K in L & M in N holds
( K *` M in L *` N & M *` K in L *` N )
proof end;

theorem :: CARD_4:83
canceled;

theorem Th84: :: CARD_4:84
for X being set st not X is finite holds
card X = omega *` (card X)
proof end;

theorem :: CARD_4:85
for X, Y being set st X <> {} & X is finite & not Y is finite holds
(card Y) *` (card X) = card Y
proof end;

theorem Th86: :: CARD_4:86
for D being non empty set
for n being Element of NAT st not D is finite & n <> 0 holds
( n -tuples_on D,D are_equipotent & card (n -tuples_on D) = card D )
proof end;

theorem :: CARD_4:87
for D being non empty set st not D is finite holds
card D = card (D *)
proof end;