Metamath Proof Explorer


Definition df-zn

Description: Define the ring of integers mod n . This is literally the quotient ring of ZZ by the ideal n ZZ , but we augment it with a total order. (Contributed by Mario Carneiro, 14-Jun-2015) (Revised by AV, 12-Jun-2019)

Ref Expression
Assertion df-zn
|- Z/nZ = ( n e. NN0 |-> [_ ZZring / z ]_ [_ ( z /s ( z ~QG ( ( RSpan ` z ) ` { n } ) ) ) / s ]_ ( s sSet <. ( le ` ndx ) , [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f ) >. ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 czn
 |-  Z/nZ
1 vn
 |-  n
2 cn0
 |-  NN0
3 czring
 |-  ZZring
4 vz
 |-  z
5 4 cv
 |-  z
6 cqus
 |-  /s
7 cqg
 |-  ~QG
8 crsp
 |-  RSpan
9 5 8 cfv
 |-  ( RSpan ` z )
10 1 cv
 |-  n
11 10 csn
 |-  { n }
12 11 9 cfv
 |-  ( ( RSpan ` z ) ` { n } )
13 5 12 7 co
 |-  ( z ~QG ( ( RSpan ` z ) ` { n } ) )
14 5 13 6 co
 |-  ( z /s ( z ~QG ( ( RSpan ` z ) ` { n } ) ) )
15 vs
 |-  s
16 15 cv
 |-  s
17 csts
 |-  sSet
18 cple
 |-  le
19 cnx
 |-  ndx
20 19 18 cfv
 |-  ( le ` ndx )
21 czrh
 |-  ZRHom
22 16 21 cfv
 |-  ( ZRHom ` s )
23 cc0
 |-  0
24 10 23 wceq
 |-  n = 0
25 cz
 |-  ZZ
26 cfzo
 |-  ..^
27 23 10 26 co
 |-  ( 0 ..^ n )
28 24 25 27 cif
 |-  if ( n = 0 , ZZ , ( 0 ..^ n ) )
29 22 28 cres
 |-  ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) )
30 vf
 |-  f
31 30 cv
 |-  f
32 cle
 |-  <_
33 31 32 ccom
 |-  ( f o. <_ )
34 31 ccnv
 |-  `' f
35 33 34 ccom
 |-  ( ( f o. <_ ) o. `' f )
36 30 29 35 csb
 |-  [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f )
37 20 36 cop
 |-  <. ( le ` ndx ) , [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f ) >.
38 16 37 17 co
 |-  ( s sSet <. ( le ` ndx ) , [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f ) >. )
39 15 14 38 csb
 |-  [_ ( z /s ( z ~QG ( ( RSpan ` z ) ` { n } ) ) ) / s ]_ ( s sSet <. ( le ` ndx ) , [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f ) >. )
40 4 3 39 csb
 |-  [_ ZZring / z ]_ [_ ( z /s ( z ~QG ( ( RSpan ` z ) ` { n } ) ) ) / s ]_ ( s sSet <. ( le ` ndx ) , [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f ) >. )
41 1 2 40 cmpt
 |-  ( n e. NN0 |-> [_ ZZring / z ]_ [_ ( z /s ( z ~QG ( ( RSpan ` z ) ` { n } ) ) ) / s ]_ ( s sSet <. ( le ` ndx ) , [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f ) >. ) )
42 0 41 wceq
 |-  Z/nZ = ( n e. NN0 |-> [_ ZZring / z ]_ [_ ( z /s ( z ~QG ( ( RSpan ` z ) ` { n } ) ) ) / s ]_ ( s sSet <. ( le ` ndx ) , [_ ( ( ZRHom ` s ) |` if ( n = 0 , ZZ , ( 0 ..^ n ) ) ) / f ]_ ( ( f o. <_ ) o. `' f ) >. ) )