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 ∈ V ↦ ( 𝑖 ∈ ( LIdeal ‘ ( Poly1𝑟 ) ) ↦ ( 𝑥 ∈ ℕ0 ↦ { 𝑗 ∣ ∃ 𝑘𝑖 ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 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 ( Poly1𝑟 )
8 7 4 cfv ( LIdeal ‘ ( Poly1𝑟 ) )
9 vx 𝑥
10 cn0 0
11 vj 𝑗
12 vk 𝑘
13 3 cv 𝑖
14 cdg1 deg1
15 6 14 cfv ( deg1𝑟 )
16 12 cv 𝑘
17 16 15 cfv ( ( deg1𝑟 ) ‘ 𝑘 )
18 cle
19 9 cv 𝑥
20 17 19 18 wbr ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥
21 11 cv 𝑗
22 cco1 coe1
23 16 22 cfv ( coe1𝑘 )
24 19 23 cfv ( ( coe1𝑘 ) ‘ 𝑥 )
25 21 24 wceq 𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 )
26 20 25 wa ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 ) )
27 26 12 13 wrex 𝑘𝑖 ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 ) )
28 27 11 cab { 𝑗 ∣ ∃ 𝑘𝑖 ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 ) ) }
29 9 10 28 cmpt ( 𝑥 ∈ ℕ0 ↦ { 𝑗 ∣ ∃ 𝑘𝑖 ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 ) ) } )
30 3 8 29 cmpt ( 𝑖 ∈ ( LIdeal ‘ ( Poly1𝑟 ) ) ↦ ( 𝑥 ∈ ℕ0 ↦ { 𝑗 ∣ ∃ 𝑘𝑖 ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 ) ) } ) )
31 1 2 30 cmpt ( 𝑟 ∈ V ↦ ( 𝑖 ∈ ( LIdeal ‘ ( Poly1𝑟 ) ) ↦ ( 𝑥 ∈ ℕ0 ↦ { 𝑗 ∣ ∃ 𝑘𝑖 ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 ) ) } ) ) )
32 0 31 wceq ldgIdlSeq = ( 𝑟 ∈ V ↦ ( 𝑖 ∈ ( LIdeal ‘ ( Poly1𝑟 ) ) ↦ ( 𝑥 ∈ ℕ0 ↦ { 𝑗 ∣ ∃ 𝑘𝑖 ( ( ( deg1𝑟 ) ‘ 𝑘 ) ≤ 𝑥𝑗 = ( ( coe1𝑘 ) ‘ 𝑥 ) ) } ) ) )