Metamath Proof Explorer


Definition df-pellfund

Description: A function mapping Pell discriminants to the corresponding fundamental solution. (Contributed by Stefan O'Rear, 18-Sep-2014) (Revised by AV, 17-Sep-2020)

Ref Expression
Assertion df-pellfund PellFund = ( 𝑥 ∈ ( ℕ ∖ ◻NN ) ↦ inf ( { 𝑧 ∈ ( Pell14QR ‘ 𝑥 ) ∣ 1 < 𝑧 } , ℝ , < ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cpellfund PellFund
1 vx 𝑥
2 cn
3 csquarenn NN
4 2 3 cdif ( ℕ ∖ ◻NN )
5 vz 𝑧
6 cpell14qr Pell14QR
7 1 cv 𝑥
8 7 6 cfv ( Pell14QR ‘ 𝑥 )
9 c1 1
10 clt <
11 5 cv 𝑧
12 9 11 10 wbr 1 < 𝑧
13 12 5 8 crab { 𝑧 ∈ ( Pell14QR ‘ 𝑥 ) ∣ 1 < 𝑧 }
14 cr
15 13 14 10 cinf inf ( { 𝑧 ∈ ( Pell14QR ‘ 𝑥 ) ∣ 1 < 𝑧 } , ℝ , < )
16 1 4 15 cmpt ( 𝑥 ∈ ( ℕ ∖ ◻NN ) ↦ inf ( { 𝑧 ∈ ( Pell14QR ‘ 𝑥 ) ∣ 1 < 𝑧 } , ℝ , < ) )
17 0 16 wceq PellFund = ( 𝑥 ∈ ( ℕ ∖ ◻NN ) ↦ inf ( { 𝑧 ∈ ( Pell14QR ‘ 𝑥 ) ∣ 1 < 𝑧 } , ℝ , < ) )