Metamath Proof Explorer


Definition df-ldgis

Description: Define a function which carries polynomial ideals to the sequence of coefficient ideals of leading coefficients of degree- x elements in the polynomial ideal. The proof that this map is strictly monotone is the core of the Hilbert Basis Theorem hbt . (Contributed by Stefan O'Rear, 31-Mar-2015)

Ref Expression
Assertion df-ldgis
|- ldgIdlSeq = ( r e. _V |-> ( i e. ( LIdeal ` ( Poly1 ` r ) ) |-> ( x e. NN0 |-> { j | E. k e. i ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) ) } ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cldgis
 |-  ldgIdlSeq
1 vr
 |-  r
2 cvv
 |-  _V
3 vi
 |-  i
4 clidl
 |-  LIdeal
5 cpl1
 |-  Poly1
6 1 cv
 |-  r
7 6 5 cfv
 |-  ( Poly1 ` r )
8 7 4 cfv
 |-  ( LIdeal ` ( Poly1 ` r ) )
9 vx
 |-  x
10 cn0
 |-  NN0
11 vj
 |-  j
12 vk
 |-  k
13 3 cv
 |-  i
14 cdg1
 |-  deg1
15 6 14 cfv
 |-  ( deg1 ` r )
16 12 cv
 |-  k
17 16 15 cfv
 |-  ( ( deg1 ` r ) ` k )
18 cle
 |-  <_
19 9 cv
 |-  x
20 17 19 18 wbr
 |-  ( ( deg1 ` r ) ` k ) <_ x
21 11 cv
 |-  j
22 cco1
 |-  coe1
23 16 22 cfv
 |-  ( coe1 ` k )
24 19 23 cfv
 |-  ( ( coe1 ` k ) ` x )
25 21 24 wceq
 |-  j = ( ( coe1 ` k ) ` x )
26 20 25 wa
 |-  ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) )
27 26 12 13 wrex
 |-  E. k e. i ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) )
28 27 11 cab
 |-  { j | E. k e. i ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) ) }
29 9 10 28 cmpt
 |-  ( x e. NN0 |-> { j | E. k e. i ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) ) } )
30 3 8 29 cmpt
 |-  ( i e. ( LIdeal ` ( Poly1 ` r ) ) |-> ( x e. NN0 |-> { j | E. k e. i ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) ) } ) )
31 1 2 30 cmpt
 |-  ( r e. _V |-> ( i e. ( LIdeal ` ( Poly1 ` r ) ) |-> ( x e. NN0 |-> { j | E. k e. i ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) ) } ) ) )
32 0 31 wceq
 |-  ldgIdlSeq = ( r e. _V |-> ( i e. ( LIdeal ` ( Poly1 ` r ) ) |-> ( x e. NN0 |-> { j | E. k e. i ( ( ( deg1 ` r ) ` k ) <_ x /\ j = ( ( coe1 ` k ) ` x ) ) } ) ) )