Metamath Proof Explorer


Theorem goldbachth

Description: Goldbach's theorem: Two different Fermat numbers are coprime. See ProofWiki "Goldbach's theorem", 31-Jul-2021, https://proofwiki.org/wiki/Goldbach%27s_Theorem or Wikipedia "Fermat number", 31-Jul-2021, https://en.wikipedia.org/wiki/Fermat_number#Basic_properties . (Contributed by AV, 1-Aug-2021)

Ref Expression
Assertion goldbachth ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ N ≠ M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1

Proof

Step Hyp Ref Expression
1 nn0re ⊢ N ∈ ℕ 0 → N ∈ ℝ
2 nn0re ⊢ M ∈ ℕ 0 → M ∈ ℝ
3 lttri4 ⊢ N ∈ ℝ ∧ M ∈ ℝ → N < M ∨ N = M ∨ M < N
4 1 2 3 syl2an ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 → N < M ∨ N = M ∨ M < N
5 4 3adant3 ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ N ≠ M → N < M ∨ N = M ∨ M < N
6 fmtnonn ⊢ N ∈ ℕ 0 → FermatNo ⁡ N ∈ ℕ
7 6 nnzd ⊢ N ∈ ℕ 0 → FermatNo ⁡ N ∈ ℤ
8 fmtnonn ⊢ M ∈ ℕ 0 → FermatNo ⁡ M ∈ ℕ
9 8 nnzd ⊢ M ∈ ℕ 0 → FermatNo ⁡ M ∈ ℤ
10 gcdcom ⊢ FermatNo ⁡ N ∈ ℤ ∧ FermatNo ⁡ M ∈ ℤ → FermatNo ⁡ N gcd FermatNo ⁡ M = FermatNo ⁡ M gcd FermatNo ⁡ N
11 7 9 10 syl2anr ⊢ M ∈ ℕ 0 ∧ N ∈ ℕ 0 → FermatNo ⁡ N gcd FermatNo ⁡ M = FermatNo ⁡ M gcd FermatNo ⁡ N
12 11 3adant3 ⊢ M ∈ ℕ 0 ∧ N ∈ ℕ 0 ∧ N < M → FermatNo ⁡ N gcd FermatNo ⁡ M = FermatNo ⁡ M gcd FermatNo ⁡ N
13 goldbachthlem2 ⊢ M ∈ ℕ 0 ∧ N ∈ ℕ 0 ∧ N < M → FermatNo ⁡ M gcd FermatNo ⁡ N = 1
14 12 13 eqtrd ⊢ M ∈ ℕ 0 ∧ N ∈ ℕ 0 ∧ N < M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
15 14 3exp ⊢ M ∈ ℕ 0 → N ∈ ℕ 0 → N < M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
16 15 impcom ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 → N < M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
17 16 3adant3 ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ N ≠ M → N < M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
18 eqneqall ⊢ N = M → N ≠ M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
19 18 com12 ⊢ N ≠ M → N = M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
20 19 3ad2ant3 ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ N ≠ M → N = M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
21 goldbachthlem2 ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ M < N → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
22 21 3expia ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 → M < N → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
23 22 3adant3 ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ N ≠ M → M < N → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
24 17 20 23 3jaod ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ N ≠ M → N < M ∨ N = M ∨ M < N → FermatNo ⁡ N gcd FermatNo ⁡ M = 1
25 5 24 mpd ⊢ N ∈ ℕ 0 ∧ M ∈ ℕ 0 ∧ N ≠ M → FermatNo ⁡ N gcd FermatNo ⁡ M = 1