Metamath Proof Explorer


Theorem pellfundex

Description: The fundamental solution as an infimum is itself a solution, showing that the solution set is discrete.

Since the fundamental solution is an infimum, there must be an element ge to Fund and lt 2*Fund. If this element is equal to the fundamental solution we're done, otherwise use the infimum again to find another element which must be ge Fund and lt the first element; their ratio is a group element in (1,2), contradicting pell14qrgapw . (Contributed by Stefan O'Rear, 18-Sep-2014)

Ref Expression
Assertion pellfundex ⊢ D ∈ ℕ ∖ ◻ ℕ → PellFund ⁡ D ∈ Pell1QR ⁡ D

Proof

Step Hyp Ref Expression
1 2re ⊢ 2 ∈ ℝ
2 pellfundre ⊢ D ∈ ℕ ∖ ◻ ℕ → PellFund ⁡ D ∈ ℝ
3 remulcl ⊢ 2 ∈ ℝ ∧ PellFund ⁡ D ∈ ℝ → 2 ⁢ PellFund ⁡ D ∈ ℝ
4 1 2 3 sylancr ⊢ D ∈ ℕ ∖ ◻ ℕ → 2 ⁢ PellFund ⁡ D ∈ ℝ
5 0red ⊢ D ∈ ℕ ∖ ◻ ℕ → 0 ∈ ℝ
6 1red ⊢ D ∈ ℕ ∖ ◻ ℕ → 1 ∈ ℝ
7 0lt1 ⊢ 0 < 1
8 7 a1i ⊢ D ∈ ℕ ∖ ◻ ℕ → 0 < 1
9 pellfundgt1 ⊢ D ∈ ℕ ∖ ◻ ℕ → 1 < PellFund ⁡ D
10 5 6 2 8 9 lttrd ⊢ D ∈ ℕ ∖ ◻ ℕ → 0 < PellFund ⁡ D
11 2 10 elrpd ⊢ D ∈ ℕ ∖ ◻ ℕ → PellFund ⁡ D ∈ ℝ +
12 2 11 ltaddrpd ⊢ D ∈ ℕ ∖ ◻ ℕ → PellFund ⁡ D < PellFund ⁡ D + PellFund ⁡ D
13 2 recnd ⊢ D ∈ ℕ ∖ ◻ ℕ → PellFund ⁡ D ∈ ℂ
14 13 2timesd ⊢ D ∈ ℕ ∖ ◻ ℕ → 2 ⁢ PellFund ⁡ D = PellFund ⁡ D + PellFund ⁡ D
15 12 14 breqtrrd ⊢ D ∈ ℕ ∖ ◻ ℕ → PellFund ⁡ D < 2 ⁢ PellFund ⁡ D
16 pellfundglb ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ 2 ⁢ PellFund ⁡ D ∈ ℝ ∧ PellFund ⁡ D < 2 ⁢ PellFund ⁡ D → ∃ a ∈ Pell1QR ⁡ D PellFund ⁡ D ≤ a ∧ a < 2 ⁢ PellFund ⁡ D
17 4 15 16 mpd3an23 ⊢ D ∈ ℕ ∖ ◻ ℕ → ∃ a ∈ Pell1QR ⁡ D PellFund ⁡ D ≤ a ∧ a < 2 ⁢ PellFund ⁡ D
18 2 adantr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → PellFund ⁡ D ∈ ℝ
19 pell1qrss14 ⊢ D ∈ ℕ ∖ ◻ ℕ → Pell1QR ⁡ D ⊆ Pell14QR ⁡ D
20 19 sselda ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → a ∈ Pell14QR ⁡ D
21 pell14qrre ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell14QR ⁡ D → a ∈ ℝ
22 20 21 syldan ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → a ∈ ℝ
23 18 22 leloed ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → PellFund ⁡ D ≤ a ↔ PellFund ⁡ D < a ∨ PellFund ⁡ D = a
24 simp-4l ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → D ∈ ℕ ∖ ◻ ℕ
25 simp-4r ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → a ∈ Pell1QR ⁡ D
26 simplr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → b ∈ Pell1QR ⁡ D
27 simprr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → b < a
28 22 ad3antrrr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → a ∈ ℝ
29 4 ad4antr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → 2 ⁢ PellFund ⁡ D ∈ ℝ
30 19 ad4antr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → Pell1QR ⁡ D ⊆ Pell14QR ⁡ D
31 30 26 sseldd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → b ∈ Pell14QR ⁡ D
32 pell14qrre ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ b ∈ Pell14QR ⁡ D → b ∈ ℝ
33 24 31 32 syl2anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → b ∈ ℝ
34 remulcl ⊢ 2 ∈ ℝ ∧ b ∈ ℝ → 2 ⁢ b ∈ ℝ
35 1 33 34 sylancr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → 2 ⁢ b ∈ ℝ
36 simprr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D → a < 2 ⁢ PellFund ⁡ D
37 36 ad2antrr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → a < 2 ⁢ PellFund ⁡ D
38 simprl ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → PellFund ⁡ D ≤ b
39 2 ad4antr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → PellFund ⁡ D ∈ ℝ
40 1 a1i ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → 2 ∈ ℝ
41 2pos ⊢ 0 < 2
42 41 a1i ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → 0 < 2
43 lemul2 ⊢ PellFund ⁡ D ∈ ℝ ∧ b ∈ ℝ ∧ 2 ∈ ℝ ∧ 0 < 2 → PellFund ⁡ D ≤ b ↔ 2 ⁢ PellFund ⁡ D ≤ 2 ⁢ b
44 39 33 40 42 43 syl112anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → PellFund ⁡ D ≤ b ↔ 2 ⁢ PellFund ⁡ D ≤ 2 ⁢ b
45 38 44 mpbid ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → 2 ⁢ PellFund ⁡ D ≤ 2 ⁢ b
46 28 29 35 37 45 ltletrd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → a < 2 ⁢ b
47 simp1 ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → D ∈ ℕ ∖ ◻ ℕ
48 19 3ad2ant1 ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → Pell1QR ⁡ D ⊆ Pell14QR ⁡ D
49 simp2l ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → a ∈ Pell1QR ⁡ D
50 48 49 sseldd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → a ∈ Pell14QR ⁡ D
51 simp2r ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → b ∈ Pell1QR ⁡ D
52 48 51 sseldd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → b ∈ Pell14QR ⁡ D
53 pell14qrdivcl ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell14QR ⁡ D ∧ b ∈ Pell14QR ⁡ D → a b ∈ Pell14QR ⁡ D
54 47 50 52 53 syl3anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → a b ∈ Pell14QR ⁡ D
55 47 52 32 syl2anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → b ∈ ℝ
56 55 recnd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → b ∈ ℂ
57 56 mullidd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → 1 ⁢ b = b
58 simp3l ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → b < a
59 57 58 eqbrtrd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → 1 ⁢ b < a
60 1red ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → 1 ∈ ℝ
61 47 50 21 syl2anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → a ∈ ℝ
62 pell14qrgt0 ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ b ∈ Pell14QR ⁡ D → 0 < b
63 47 52 62 syl2anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → 0 < b
64 ltmuldiv ⊢ 1 ∈ ℝ ∧ a ∈ ℝ ∧ b ∈ ℝ ∧ 0 < b → 1 ⁢ b < a ↔ 1 < a b
65 60 61 55 63 64 syl112anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → 1 ⁢ b < a ↔ 1 < a b
66 59 65 mpbid ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → 1 < a b
67 simp3r ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → a < 2 ⁢ b
68 1 a1i ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → 2 ∈ ℝ
69 ltdivmul2 ⊢ a ∈ ℝ ∧ 2 ∈ ℝ ∧ b ∈ ℝ ∧ 0 < b → a b < 2 ↔ a < 2 ⁢ b
70 61 68 55 63 69 syl112anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → a b < 2 ↔ a < 2 ⁢ b
71 67 70 mpbird ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → a b < 2
72 simprr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → a b < 2
73 simpll ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → D ∈ ℕ ∖ ◻ ℕ
74 simplr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → a b ∈ Pell14QR ⁡ D
75 simprl ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → 1 < a b
76 pell14qrgapw ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b → 2 < a b
77 73 74 75 76 syl3anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → 2 < a b
78 pell14qrre ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D → a b ∈ ℝ
79 78 adantr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → a b ∈ ℝ
80 ltnsym ⊢ 2 ∈ ℝ ∧ a b ∈ ℝ → 2 < a b → ¬ a b < 2
81 1 79 80 sylancr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → 2 < a b → ¬ a b < 2
82 77 81 mpd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → ¬ a b < 2
83 72 82 pm2.21dd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a b ∈ Pell14QR ⁡ D ∧ 1 < a b ∧ a b < 2 → PellFund ⁡ D ∈ Pell1QR ⁡ D
84 47 54 66 71 83 syl22anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ b < a ∧ a < 2 ⁢ b → PellFund ⁡ D ∈ Pell1QR ⁡ D
85 24 25 26 27 46 84 syl122anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D ∧ b ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D ≤ b ∧ b < a → PellFund ⁡ D ∈ Pell1QR ⁡ D
86 simpll ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D → D ∈ ℕ ∖ ◻ ℕ
87 22 adantr ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D → a ∈ ℝ
88 simprl ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D < a
89 pellfundglb ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ ℝ ∧ PellFund ⁡ D < a → ∃ b ∈ Pell1QR ⁡ D PellFund ⁡ D ≤ b ∧ b < a
90 86 87 88 89 syl3anc ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D → ∃ b ∈ Pell1QR ⁡ D PellFund ⁡ D ≤ b ∧ b < a
91 85 90 r19.29a ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D < a ∧ a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
92 91 exp32 ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → PellFund ⁡ D < a → a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
93 simp2 ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D = a ∧ a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D = a
94 simp1r ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D = a ∧ a < 2 ⁢ PellFund ⁡ D → a ∈ Pell1QR ⁡ D
95 93 94 eqeltrd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D ∧ PellFund ⁡ D = a ∧ a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
96 95 3exp ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → PellFund ⁡ D = a → a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
97 92 96 jaod ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → PellFund ⁡ D < a ∨ PellFund ⁡ D = a → a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
98 23 97 sylbid ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → PellFund ⁡ D ≤ a → a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
99 98 impd ⊢ D ∈ ℕ ∖ ◻ ℕ ∧ a ∈ Pell1QR ⁡ D → PellFund ⁡ D ≤ a ∧ a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
100 99 rexlimdva ⊢ D ∈ ℕ ∖ ◻ ℕ → ∃ a ∈ Pell1QR ⁡ D PellFund ⁡ D ≤ a ∧ a < 2 ⁢ PellFund ⁡ D → PellFund ⁡ D ∈ Pell1QR ⁡ D
101 17 100 mpd ⊢ D ∈ ℕ ∖ ◻ ℕ → PellFund ⁡ D ∈ Pell1QR ⁡ D