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Theorem setrec1 42438
Description: This is the first of two fundamental theorems about set recursion from which all other facts will be derived. It states that the class setrecs ( F ) is closed under  F. This effectively sets the actual value of setrecs ( F ) as a lower bound for setrecs ( F ), as it implies that any set generated by successive applications of  F is a member of  B. This theorem "gets off the ground" because we can start by letting  A  =  (/), and the hypotheses of the theorem will hold trivially.

Variable  B represents an abbreviation of setrecs
( F ) or another name of setrecs ( F ) (for an example of the latter, see theorem setrecon).

Proof summary: Assume that 
A  C_  B, meaning that all elements of  A are in some set recursively generated by  F. Then by setrec1lem3 42436, 
A is a subset of some set recursively generated by  F. (It turns out that  A itself is recursively generated by  F, but we don't need this fact. See the comment to setrec1lem3 42436.) Therefore, by setrec1lem4 42437, 
( F `  A
) is a subset of some set recursively generated by  F. Thus, by ssuni 4459, it is a subset of the union of all sets recursively generated by  F.

See df-setrecs 42431 for a detailed description of how the setrecs definition works.

(Contributed by Emmett Weisz, 9-Oct-2020.)

Hypotheses
Ref Expression
setrec1.b  |-  B  = setrecs
( F )
setrec1.v  |-  ( ph  ->  A  e.  _V )
setrec1.a  |-  ( ph  ->  A  C_  B )
Assertion
Ref Expression
setrec1  |-  ( ph  ->  ( F `  A
)  C_  B )

Proof of Theorem setrec1
Dummy variables  x  a  w  y  z are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eqid 2622 . . . 4  |-  { y  |  A. z ( A. w ( w 
C_  y  ->  (
w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) }  =  {
y  |  A. z
( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) }
2 setrec1.v . . . 4  |-  ( ph  ->  A  e.  _V )
3 setrec1.a . . . . . . . . 9  |-  ( ph  ->  A  C_  B )
43sseld 3602 . . . . . . . 8  |-  ( ph  ->  ( a  e.  A  ->  a  e.  B ) )
54imp 445 . . . . . . 7  |-  ( (
ph  /\  a  e.  A )  ->  a  e.  B )
6 setrec1.b . . . . . . . 8  |-  B  = setrecs
( F )
7 df-setrecs 42431 . . . . . . . 8  |- setrecs ( F )  =  U. {
y  |  A. z
( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) }
86, 7eqtri 2644 . . . . . . 7  |-  B  = 
U. { y  | 
A. z ( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w )  C_  z
) )  ->  y  C_  z ) }
95, 8syl6eleq 2711 . . . . . 6  |-  ( (
ph  /\  a  e.  A )  ->  a  e.  U. { y  | 
A. z ( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w )  C_  z
) )  ->  y  C_  z ) } )
10 eluni 4439 . . . . . 6  |-  ( a  e.  U. { y  |  A. z ( A. w ( w 
C_  y  ->  (
w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) }  <->  E. x
( a  e.  x  /\  x  e.  { y  |  A. z ( A. w ( w 
C_  y  ->  (
w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } ) )
119, 10sylib 208 . . . . 5  |-  ( (
ph  /\  a  e.  A )  ->  E. x
( a  e.  x  /\  x  e.  { y  |  A. z ( A. w ( w 
C_  y  ->  (
w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } ) )
1211ralrimiva 2966 . . . 4  |-  ( ph  ->  A. a  e.  A  E. x ( a  e.  x  /\  x  e. 
{ y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )
131, 2, 12setrec1lem3 42436 . . 3  |-  ( ph  ->  E. x ( A 
C_  x  /\  x  e.  { y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )
14 nfv 1843 . . . . . . 7  |-  F/ z
ph
15 nfv 1843 . . . . . . . 8  |-  F/ z  A  C_  x
16 nfaba1 2770 . . . . . . . . 9  |-  F/_ z { y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) }
1716nfel2 2781 . . . . . . . 8  |-  F/ z  x  e.  { y  |  A. z ( A. w ( w 
C_  y  ->  (
w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) }
1815, 17nfan 1828 . . . . . . 7  |-  F/ z ( A  C_  x  /\  x  e.  { y  |  A. z ( A. w ( w 
C_  y  ->  (
w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } )
1914, 18nfan 1828 . . . . . 6  |-  F/ z ( ph  /\  ( A  C_  x  /\  x  e.  { y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )
202adantr 481 . . . . . 6  |-  ( (
ph  /\  ( A  C_  x  /\  x  e. 
{ y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )  ->  A  e.  _V )
21 simprl 794 . . . . . 6  |-  ( (
ph  /\  ( A  C_  x  /\  x  e. 
{ y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )  ->  A  C_  x
)
22 simprr 796 . . . . . 6  |-  ( (
ph  /\  ( A  C_  x  /\  x  e. 
{ y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )  ->  x  e.  { y  |  A. z
( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } )
2319, 1, 20, 21, 22setrec1lem4 42437 . . . . 5  |-  ( (
ph  /\  ( A  C_  x  /\  x  e. 
{ y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )  ->  ( x  u.  ( F `  A
) )  e.  {
y  |  A. z
( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } )
24 ssun2 3777 . . . . 5  |-  ( F `
 A )  C_  ( x  u.  ( F `  A )
)
2523, 24jctil 560 . . . 4  |-  ( (
ph  /\  ( A  C_  x  /\  x  e. 
{ y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )  ->  ( ( F `  A )  C_  ( x  u.  ( F `  A )
)  /\  ( x  u.  ( F `  A
) )  e.  {
y  |  A. z
( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } ) )
26 ssuni 4459 . . . 4  |-  ( ( ( F `  A
)  C_  ( x  u.  ( F `  A
) )  /\  (
x  u.  ( F `
 A ) )  e.  { y  | 
A. z ( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w )  C_  z
) )  ->  y  C_  z ) } )  ->  ( F `  A )  C_  U. {
y  |  A. z
( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } )
2725, 26syl 17 . . 3  |-  ( (
ph  /\  ( A  C_  x  /\  x  e. 
{ y  |  A. z ( A. w
( w  C_  y  ->  ( w  C_  z  ->  ( F `  w
)  C_  z )
)  ->  y  C_  z ) } ) )  ->  ( F `  A )  C_  U. {
y  |  A. z
( A. w ( w  C_  y  ->  ( w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } )
2813, 27exlimddv 1863 . 2  |-  ( ph  ->  ( F `  A
)  C_  U. { y  |  A. z ( A. w ( w 
C_  y  ->  (
w  C_  z  ->  ( F `  w ) 
C_  z ) )  ->  y  C_  z
) } )
2928, 8syl6sseqr 3652 1  |-  ( ph  ->  ( F `  A
)  C_  B )
Colors of variables: wff setvar class
Syntax hints:    -> wi 4    /\ wa 384   A.wal 1481    = wceq 1483   E.wex 1704    e. wcel 1990   {cab 2608   _Vcvv 3200    u. cun 3572    C_ wss 3574   U.cuni 4436   ` cfv 5888  setrecscsetrecs 42430
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-rep 4771  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-reg 8497  ax-inf2 8538
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-pss 3590  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-tp 4182  df-op 4184  df-uni 4437  df-int 4476  df-iun 4522  df-iin 4523  df-br 4654  df-opab 4713  df-mpt 4730  df-tr 4753  df-id 5024  df-eprel 5029  df-po 5035  df-so 5036  df-fr 5073  df-we 5075  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-pred 5680  df-ord 5726  df-on 5727  df-lim 5728  df-suc 5729  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-om 7066  df-wrecs 7407  df-recs 7468  df-rdg 7506  df-r1 8627  df-rank 8628  df-setrecs 42431
This theorem is referenced by:  elsetrecslem  42444  elsetrecs  42445  vsetrec  42446  onsetrec  42451
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