Definition df-gbo 42424

Description: Define the set of (strong) odd Goldbach numbers, which are positive odd integers that can be expressed as the sum of three odd primes. By this definition, the strong ternary Goldbach conjecture can be expressed as ∀𝑚 ∈ Odd (7 < 𝑚 → 𝑚 ∈ GoldbachOdd ). (Contributed by AV, 26-Jul-2020.)

Assertion

Ref	Expression
df-gbo	⊢ GoldbachOdd = {𝑧 ∈ Odd ∣ ∃𝑝 ∈ ℙ ∃𝑞 ∈ ℙ ∃𝑟 ∈ ℙ ((𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd ) ∧ 𝑧 = ((𝑝 + 𝑞) + 𝑟))}

Distinct variable group:   𝑧,𝑝,𝑞,𝑟

Detailed syntax breakdown of Definition df-gbo

Step	Hyp	Ref	Expression
1		cgbo 42421	. 2 class GoldbachOdd
2		vp	. . . . . . . . . 10 setvar 𝑝
3	2	cv 1652	. . . . . . . . 9 class 𝑝
4		codd 42324	. . . . . . . . 9 class Odd
5	3, 4	wcel 2157	. . . . . . . 8 wff 𝑝 ∈ Odd
6		vq	. . . . . . . . . 10 setvar 𝑞
7	6	cv 1652	. . . . . . . . 9 class 𝑞
8	7, 4	wcel 2157	. . . . . . . 8 wff 𝑞 ∈ Odd
9		vr	. . . . . . . . . 10 setvar 𝑟
10	9	cv 1652	. . . . . . . . 9 class 𝑟
11	10, 4	wcel 2157	. . . . . . . 8 wff 𝑟 ∈ Odd
12	5, 8, 11	w3a 1108	. . . . . . 7 wff (𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd )
13		vz	. . . . . . . . 9 setvar 𝑧
14	13	cv 1652	. . . . . . . 8 class 𝑧
15		caddc 10231	. . . . . . . . . 10 class +
16	3, 7, 15	co 6882	. . . . . . . . 9 class (𝑝 + 𝑞)
17	16, 10, 15	co 6882	. . . . . . . 8 class ((𝑝 + 𝑞) + 𝑟)
18	14, 17	wceq 1653	. . . . . . 7 wff 𝑧 = ((𝑝 + 𝑞) + 𝑟)
19	12, 18	wa 385	. . . . . 6 wff ((𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd ) ∧ 𝑧 = ((𝑝 + 𝑞) + 𝑟))
20		cprime 15723	. . . . . 6 class ℙ
21	19, 9, 20	wrex 3094	. . . . 5 wff ∃𝑟 ∈ ℙ ((𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd ) ∧ 𝑧 = ((𝑝 + 𝑞) + 𝑟))
22	21, 6, 20	wrex 3094	. . . 4 wff ∃𝑞 ∈ ℙ ∃𝑟 ∈ ℙ ((𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd ) ∧ 𝑧 = ((𝑝 + 𝑞) + 𝑟))
23	22, 2, 20	wrex 3094	. . 3 wff ∃𝑝 ∈ ℙ ∃𝑞 ∈ ℙ ∃𝑟 ∈ ℙ ((𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd ) ∧ 𝑧 = ((𝑝 + 𝑞) + 𝑟))
24	23, 13, 4	crab 3097	. 2 class {𝑧 ∈ Odd ∣ ∃𝑝 ∈ ℙ ∃𝑞 ∈ ℙ ∃𝑟 ∈ ℙ ((𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd ) ∧ 𝑧 = ((𝑝 + 𝑞) + 𝑟))}
25	1, 24	wceq 1653	1 wff GoldbachOdd = {𝑧 ∈ Odd ∣ ∃𝑝 ∈ ℙ ∃𝑞 ∈ ℙ ∃𝑟 ∈ ℙ ((𝑝 ∈ Odd ∧ 𝑞 ∈ Odd ∧ 𝑟 ∈ Odd ) ∧ 𝑧 = ((𝑝 + 𝑞) + 𝑟))}

This definition is referenced by:  isgbo  42427  tgoldbachgtALTV  42486