Metamath Proof Explorer


Definition df-mri

Description: In a Moore system, a set isindependent if no element of the set is in the closure of the set with the element removed (Section 0.6 in Gratzer p. 27; Definition 4.1.1 in FaureFrolicher p. 83.) mrInd is a class function which takes a Moore system to its set of independent sets. (Contributed by David Moews, 1-May-2017)

Ref Expression
Assertion df-mri
|- mrInd = ( c e. U. ran Moore |-> { s e. ~P U. c | A. x e. s -. x e. ( ( mrCls ` c ) ` ( s \ { x } ) ) } )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cmri
 |-  mrInd
1 vc
 |-  c
2 cmre
 |-  Moore
3 2 crn
 |-  ran Moore
4 3 cuni
 |-  U. ran Moore
5 vs
 |-  s
6 1 cv
 |-  c
7 6 cuni
 |-  U. c
8 7 cpw
 |-  ~P U. c
9 vx
 |-  x
10 5 cv
 |-  s
11 9 cv
 |-  x
12 cmrc
 |-  mrCls
13 6 12 cfv
 |-  ( mrCls ` c )
14 11 csn
 |-  { x }
15 10 14 cdif
 |-  ( s \ { x } )
16 15 13 cfv
 |-  ( ( mrCls ` c ) ` ( s \ { x } ) )
17 11 16 wcel
 |-  x e. ( ( mrCls ` c ) ` ( s \ { x } ) )
18 17 wn
 |-  -. x e. ( ( mrCls ` c ) ` ( s \ { x } ) )
19 18 9 10 wral
 |-  A. x e. s -. x e. ( ( mrCls ` c ) ` ( s \ { x } ) )
20 19 5 8 crab
 |-  { s e. ~P U. c | A. x e. s -. x e. ( ( mrCls ` c ) ` ( s \ { x } ) ) }
21 1 4 20 cmpt
 |-  ( c e. U. ran Moore |-> { s e. ~P U. c | A. x e. s -. x e. ( ( mrCls ` c ) ` ( s \ { x } ) ) } )
22 0 21 wceq
 |-  mrInd = ( c e. U. ran Moore |-> { s e. ~P U. c | A. x e. s -. x e. ( ( mrCls ` c ) ` ( s \ { x } ) ) } )