Definition df-mplcoe 14941

Description: Define the subalgebra of the power series algebra generated by the variables; this is the polynomial algebra (the set of power series with finite degree).

The index set (which has an element for each variable) is 𝑖, the coefficients are in ring 𝑟, and for each variable there is a "degree" such that the coefficient is zero for a term where the powers are all greater than those degrees. (Degree is in quotes because there is no guarantee that coefficients below that degree are nonzero, as we do not assume decidable equality for 𝑟). (Contributed by Mario Carneiro, 7-Jan-2015.) (Revised by AV, 25-Jun-2019.) (Revised by Jim Kingdon, 7-Oct-2025.)

Assertion

Ref	Expression
df-mplcoe	⊢ mPoly = (𝑖 ∈ V, 𝑟 ∈ V ↦ ⦋(𝑖 mPwSer 𝑟) / 𝑤⦌(𝑤 ↾s {𝑓 ∈ (Base‘𝑤) ∣ ∃𝑎 ∈ (ℕ0 ↑𝑚 𝑖)∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))}))

Distinct variable group:   𝑎,𝑏,𝑓,𝑖,𝑘,𝑟,𝑤

Detailed syntax breakdown of Definition df-mplcoe

Step	Hyp	Ref	Expression
1		cmpl 14939	. 2 class mPoly
2		vi	. . 3 setvar 𝑖
3		vr	. . 3 setvar 𝑟
4		cvv 2815	. . 3 class V
5		vw	. . . 4 setvar 𝑤
6	2	cv 1397	. . . . 5 class 𝑖
7	3	cv 1397	. . . . 5 class 𝑟
8		cmps 14938	. . . . 5 class mPwSer
9	6, 7, 8	co 6058	. . . 4 class (𝑖 mPwSer 𝑟)
10	5	cv 1397	. . . . 5 class 𝑤
11		vk	. . . . . . . . . . . . 13 setvar 𝑘
12	11	cv 1397	. . . . . . . . . . . 12 class 𝑘
13		va	. . . . . . . . . . . . 13 setvar 𝑎
14	13	cv 1397	. . . . . . . . . . . 12 class 𝑎
15	12, 14	cfv 5357	. . . . . . . . . . 11 class (𝑎‘𝑘)
16		vb	. . . . . . . . . . . . 13 setvar 𝑏
17	16	cv 1397	. . . . . . . . . . . 12 class 𝑏
18	12, 17	cfv 5357	. . . . . . . . . . 11 class (𝑏‘𝑘)
19		clt 8324	. . . . . . . . . . 11 class <
20	15, 18, 19	wbr 4114	. . . . . . . . . 10 wff (𝑎‘𝑘) < (𝑏‘𝑘)
21	20, 11, 6	wral 2522	. . . . . . . . 9 wff ∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘)
22		vf	. . . . . . . . . . . 12 setvar 𝑓
23	22	cv 1397	. . . . . . . . . . 11 class 𝑓
24	17, 23	cfv 5357	. . . . . . . . . 10 class (𝑓‘𝑏)
25		c0g 13556	. . . . . . . . . . 11 class 0g
26	7, 25	cfv 5357	. . . . . . . . . 10 class (0g‘𝑟)
27	24, 26	wceq 1398	. . . . . . . . 9 wff (𝑓‘𝑏) = (0g‘𝑟)
28	21, 27	wi 4	. . . . . . . 8 wff (∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))
29		cn0 9516	. . . . . . . . 9 class ℕ0
30		cmap 6895	. . . . . . . . 9 class ↑𝑚
31	29, 6, 30	co 6058	. . . . . . . 8 class (ℕ0 ↑𝑚 𝑖)
32	28, 16, 31	wral 2522	. . . . . . 7 wff ∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))
33	32, 13, 31	wrex 2523	. . . . . 6 wff ∃𝑎 ∈ (ℕ0 ↑𝑚 𝑖)∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))
34		cbs 13299	. . . . . . 7 class Base
35	10, 34	cfv 5357	. . . . . 6 class (Base‘𝑤)
36	33, 22, 35	crab 2526	. . . . 5 class {𝑓 ∈ (Base‘𝑤) ∣ ∃𝑎 ∈ (ℕ0 ↑𝑚 𝑖)∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))}
37		cress 13300	. . . . 5 class ↾s
38	10, 36, 37	co 6058	. . . 4 class (𝑤 ↾s {𝑓 ∈ (Base‘𝑤) ∣ ∃𝑎 ∈ (ℕ0 ↑𝑚 𝑖)∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))})
39	5, 9, 38	csb 3141	. . 3 class ⦋(𝑖 mPwSer 𝑟) / 𝑤⦌(𝑤 ↾s {𝑓 ∈ (Base‘𝑤) ∣ ∃𝑎 ∈ (ℕ0 ↑𝑚 𝑖)∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))})
40	2, 3, 4, 4, 39	cmpo 6060	. 2 class (𝑖 ∈ V, 𝑟 ∈ V ↦ ⦋(𝑖 mPwSer 𝑟) / 𝑤⦌(𝑤 ↾s {𝑓 ∈ (Base‘𝑤) ∣ ∃𝑎 ∈ (ℕ0 ↑𝑚 𝑖)∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))}))
41	1, 40	wceq 1398	1 wff mPoly = (𝑖 ∈ V, 𝑟 ∈ V ↦ ⦋(𝑖 mPwSer 𝑟) / 𝑤⦌(𝑤 ↾s {𝑓 ∈ (Base‘𝑤) ∣ ∃𝑎 ∈ (ℕ0 ↑𝑚 𝑖)∀𝑏 ∈ (ℕ0 ↑𝑚 𝑖)(∀𝑘 ∈ 𝑖 (𝑎‘𝑘) < (𝑏‘𝑘) → (𝑓‘𝑏) = (0g‘𝑟))}))

This definition is referenced by:  reldmmpl  14973  mplvalcoe  14974  fnmpl  14977